/* isbc208.c: Intel iSBC208 Floppy Disk adapter | |
Copyright (c) 2011, William A. Beech | |
Permission is hereby granted, free of charge, to any person obtaining a | |
copy of this software and associated documentation files (the "Software"), | |
to deal in the Software without restriction, including without limitation | |
the rights to use, copy, modify, merge, publish, distribute, sublicense, | |
and/or sell copies of the Software, and to permit persons to whom the | |
Software is furnished to do so, subject to the following conditions: | |
The above copyright notice and this permission notice shall be included in | |
all copies or substantial portions of the Software. | |
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL | |
WILLIAM A. BEECH BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER | |
IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN | |
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. | |
Except as contained in this notice, the name of William A. Beech shall not be | |
used in advertising or otherwise to promote the sale, use or other dealings | |
in this Software without prior written authorization from William A. Beech. | |
MODIFICATIONS: | |
?? ??? 11 - Original file. | |
24 Apr 15 -- Modified to use simh_debug | |
NOTES: | |
These functions support a simulated iSBC208 interface to 4 each 8-, 5 1/4-, or | |
3 1/2-inch floppy disk drives. Commands are setup with programmed I/O to the | |
simulated ports of an i8237 DMA controller and an i8272 FDC. Data transfer | |
to/from the simulated disks is performed directly with the multibus memory. | |
The iSBC-208 can be configured for 8- or 16-bit addresses. It defaults to 8-bit | |
addresses for the 8080/8085 processors. It can be configured for I/O port | |
addresses with 3-bits (8-bit address) or 11-bits (16-bit address). Default is | |
3-bits set to 0. This defines the port offset to be used to determine the actual | |
port address. Bus priority can be configured for parallel or serial mode. Default is | |
serial. The multibus interface interrupt can be configured for interrupt 0-7. | |
Default is none. Since all channel registers in the i8237 are 16-bit, transfers | |
are done as two 8-bit operations, low- then high-byte. | |
Port addressing is as follows (Port offset = 0): | |
Port Mode Command Function | |
00 Write Load DMAC Channel 0 Base and Current Address Regsiters | |
Read Read DMAC Channel 0 Current Address Register | |
01 Write Load DMAC Channel 0 Base and Current Word Count Registers | |
Read Read DMAC Channel 0 Current Word Count Register | |
04 Write Load DMAC Channel 2 Base and Current Address Regsiters | |
Read Read DMAC Channel 2 Current Address Register | |
05 Write Load DMAC Channel 2 Base and Current Word Count Registers | |
Read Read DMAC Channel 2 Current Word Count Register | |
06 Write Load DMAC Channel 3 Base and Current Address Regsiters | |
Read Read DMAC Channel 3 Current Address Register | |
07 Write Load DMAC Channel 3 Base and Current Word Count Registers | |
Read Read DMAC Channel 3 Current Word Count Register | |
08 Write Load DMAC Command Register | |
Read Read DMAC Status Register | |
09 Write Load DMAC Request Register | |
OA Write Set/Reset DMAC Mask Register | |
OB Write Load DMAC Mode Register | |
OC Write Clear DMAC First/Last Flip-Flop | |
0D Write DMAC Master Clear | |
OF Write Load DMAC Mask Register | |
10 Read Read FDC Status Register | |
11 Write Load FDC Data Register | |
Read Read FDC Data Register | |
12 Write Load Controller Auxiliary Port | |
Read Poll Interrupt Status | |
13 Write Controller Reset | |
14 Write Load Controller Low-Byte Segment Address Register | |
15 Write Load Controller High-Byte Segment Address Register | |
20-2F Read/Write Reserved for iSBX Multimodule Board | |
Register usage is defined in the following paragraphs. | |
Read/Write DMAC Address Registers | |
Used to simultaneously load a channel's current-address register and base-address | |
register with the memory address of the first byte to be transferred. (The Channel | |
0 current/base address register must be loaded prior to initiating a diskette read | |
or write operation.) Since each channel's address registers are 16 bits in length | |
(64K address range), two "write address register" commands must be executed in | |
order to load the complete current/base address registers for any channel. | |
Read/Write DMAC Word Count Registers | |
The Write DMAC Word Count Register command is used to simultaneously load a | |
channel's current and base word-count registers with the number of bytes | |
to be transferred during a subsequent DMA operation. Since the word-count | |
registers are 16-bits in length, two commands must be executed to load both | |
halves of the registers. | |
Write DMAC Command Register | |
The Write DMAC Command Register command loads an 8-bit byte into the | |
DMAC's command register to define the operating characteristics of the | |
DMAC. The functions of the individual bits in the command register are | |
defined in the following diagram. Note that only two bits within the | |
register are applicable to the controller; the remaining bits select | |
functions that are not supported and, accordingly, must always be set | |
to zero. | |
7 6 5 4 3 2 1 0 | |
+---+---+---+---+---+---+---+---+ | |
| 0 0 0 0 0 0 | | |
+---+---+---+---+---+---+---+---+ | |
| | | |
| +---------- 0 CONTROLLER ENABLE | |
| 1 CONTROLLER DISABLE | |
| | |
+------------------ 0 FIXED PRIORITY | |
1 ROTATING PRIORITY | |
Read DMAC Status Register Command | |
The Read DMAC Status Register command accesses an 8-bit status byte that | |
identifies the DMA channels that have reached terminal count or that | |
have a pending DMA request. | |
7 6 5 4 3 2 1 0 | |
+---+---+---+---+---+---+---+---+ | |
| 0 0 | | |
+---+---+---+---+---+---+---+---+ | |
| | | | | | | |
| | | | | +-- CHANNEL 0 TC | |
| | | | +---------- CHANNEL 2 TC | |
| | | +-------------- CHANNEL 3 TC | |
| | +------------------ CHANNEL 0 DMA REQUEST | |
| +-------------------------- CHANNEL 2 DMA REQUEST | |
+------------------------------ CHANNEL 3 DMA REQUEST | |
Write DMAC Request Register | |
The data byte associated with the Write DMAC Request Register command | |
sets or resets a channel's associated request bit within the DMAC's | |
internal 4-bit request register. | |
7 6 5 4 3 2 1 0 | |
+---+---+---+---+---+---+---+---+ | |
| X X X X X | | |
+---+---+---+---+---+---+---+---+ | |
| | | | |
| +---+-- 00 SELECT CHANNEL 0 | |
| 01 SELECT CHANNEL 1 | |
| 10 SELECT CHANNEL 2 | |
| 11 SELECT CHANNEL 3 | |
| | |
+---------- 0 RESET REQUEST BIT | |
1 SET REQUEST BIT | |
Set/Reset DMAC Mask Register | |
Prior to a DREQ-initiated DMA transfer, the channel's mask bit must | |
be reset to enable recognition of the DREQ input. When the transfer | |
is complete (terminal count reached or external EOP applied) and | |
the channel is not programmed to autoinitialize, the channel's | |
mask bit is automatically set (disabling DREQ) and must be reset | |
prior to a subsequent DMA transfer. All four bits of the mask | |
register are set (disabling the DREQ inputs) by a DMAC master | |
clear or controller reset. Additionally, all four bits can be | |
set/reset by a single Write DMAC Mask Register command. | |
7 6 5 4 3 2 1 0 | |
+---+---+---+---+---+---+---+---+ | |
| X X X X X | | |
+---+---+---+---+---+---+---+---+ | |
| | | | |
| +---+-- 00 SELECT CHANNEL 0 | |
| 01 SELECT CHANNEL 1 | |
| 10 SELECT CHANNEL 2 | |
| 11 SELECT CHANNEL 3 | |
| | |
+---------- 0 RESET REQUEST BIT | |
1 SET REQUEST BIT | |
Write DMAC Mode Register | |
The Write DMAC Mode Register command is used to define the | |
operating mode characteristics for each DMA channel. Each | |
channel has an internal 6-bit mode register; the high-order | |
six bits of the associated data byte are written into the | |
mode register addressed by the two low-order bits. | |
7 6 5 4 3 2 1 0 | |
+---+---+---+---+---+---+---+---+ | |
| | | |
+---+---+---+---+---+---+---+---+ | |
| | | | | | | | | |
| | | | | | +---+-- 00 SELECT CHANNEL 0 | |
| | | | | | 01 SELECT CHANNEL 1 | |
| | | | | | 10 SELECT CHANNEL 2 | |
| | | | | | 11 SELECT CHANNEL 3 | |
| | | | | | | |
| | | | +---+---------- 00 VERIFY TRANSFER | |
| | | | 01 WRITE TRANSFER | |
| | | | 10 READ TRANSFER | |
| | | | | |
| | | +------------------ 0 AUTOINITIALIZE DISABLE | |
| | | 1 AUTOINITIALIZE ENABLE | |
| | | | |
| | +---------------------- 0 ADDRESS INCREMENT | |
| | 1 ADDRESS DECREMENT | |
| | | |
+---+-------------------------- 00 DEMAND MODE | |
01 SINGLE MODE | |
10 BLOCK MODE | |
Clear DMAC First/Last Flip-Flop | |
The Clear DMAC First/Last Flip-Flop command initializes | |
the DMAC's internal first/last flip-flop so that the | |
next byte written to or re~d from the 16-bit address | |
or word-count registers is the low-order byte. The | |
flip-flop is toggled with each register access so that | |
a second register read or write command accesses the | |
high-order byte. | |
DMAC Master Clear | |
The DMAC Master Clear command clears the DMAC's command, status, | |
request, and temporary registers to zero, initializes the | |
first/last flip-flop, and sets the four channel mask bits in | |
the mask register to disable all DMA requests (i.e., the DMAC | |
is placed in an idle state). | |
Write DMAC Mask Register | |
The Write DMAC Mask Register command allows all four bits of the | |
DMAC's mask register to be written with a single command. | |
7 6 5 4 3 2 1 0 | |
+---+---+---+---+---+---+---+---+ | |
| X X X X X | | |
+---+---+---+---+---+---+---+---+ | |
| | | | |
| | +-- 0 CLEAR CHANNEL 0 MASK BIT | |
| | 1 SET CHANNEL 0 MASK BIT | |
| | | |
| +---------- 0 CLEAR CHANNEL 2 MASK BIT | |
| 1 SET CHANNEL 2 MASK BIT | |
| | |
+-------------- 0 CLEAR CHANNEL 3 MASK BIT | |
1 SET CHANNEL 3 MASK BIT | |
Read FDC Status Register | |
The Read FDC Status Register command accesses the FDC's main | |
status register. The individual status register bits are as | |
follows: | |
7 6 5 4 3 2 1 0 | |
+---+---+---+---+---+---+---+---+ | |
| | | |
+---+---+---+---+---+---+---+---+ | |
| | | | | | | | | |
| | | | | | | +-- FDD 0 BUSY | |
| | | | | | +------ FDD 1 BUSY | |
| | | | | +---------- FDD 2 BUSY | |
| | | | +-------------- FDD 3 BUSY | |
| | | +------------------ FDC BUSY | |
| | +---------------------- NON-DMA MODE | |
| +-------------------------- DATA INPUT/OUTPUT | |
+------------------------------ REQUEST FOR MASTER | |
Read/Write FDC Data Register | |
The Read and Write FDC Data Register commands are used to write | |
command and parameter bytes to the FDC in order to specify the | |
operation to be performed (referred to as the "command phase") | |
and to read status bytes from the FDC following the operation | |
(referred to as the "result phase"). During the command and | |
result phases, the 8-bit data register is actually a series of | |
8-bit registers in a stack. Each register is accessed in | |
sequence; the number of registers accessed and the individual | |
register contents are defined by the specific disk command. | |
Write Controller Auxiliary Port | |
The Write Controller Auxiliary Port command is used to set or | |
clear individual bits within the controller's auxiliary port. | |
The four low-order port bits are dedicated to auxiliary drive | |
control functions (jumper links are required to connect the | |
desired port bit to an available pin on the drive interface | |
connectors). The most common application for these bits is | |
the "Motor-On" control function for mini-sized drives. | |
7 6 5 4 3 2 1 0 | |
+---+---+---+---+---+---+---+---+ | |
| | | |
+---+---+---+---+---+---+---+---+ | |
| | | | | | | | | |
| | | | +---+---+---+-- DRIVE CONTROL | |
| | | +------------------ ADDR 20 | |
| | +---------------------- ADDR 21 | |
| +-------------------------- ADDR 22 | |
+------------------------------ ADDR 23 | |
Poll Interrupt Status | |
The Poll Interrupt Status command presents the interrupt | |
status of the controller and the two interrupt status | |
lines dedicated to the iSBX Multimodule board. | |
7 6 5 4 3 2 1 0 | |
+---+---+---+---+---+---+---+---+ | |
| X X X X X | | |
+---+---+---+---+---+---+---+---+ | |
| | | | |
| | +-- CONTROLLER INTERRUPT | |
| +------ MULTIMODULE BOARD INTERRUPT 0 | |
+---------- MULTIMODULE BOARD INTERRUPT 1 | |
Controller Reset | |
The Controller Reset command is the software reset for the | |
controller. This command clears the controller's auxiliary | |
port and segment address register, provides a reset signal | |
to the iSBX Multimodule board and initializes the bus | |
controller (releases the bus), the DMAC (clears the internal | |
registers and masks the DREQ inputs), and the FDC (places | |
the FDC in an idle state and disables the output control | |
lines to the diskette drive). | |
Write Controller Low- And High-Byte Segment Address Registers | |
The Write Controller Low- and High-Byte Address Registers | |
commands are required when the controller uses 20-bit | |
addressing (memory address range from 0 to OFFFFFH). These | |
commands are issued prior to initiating a diskette read or | |
write operation to specify the 16-bit segment address. | |
FDC Commands | |
The 8272/D765 is capable of performing 15 different | |
commands. Each command is initiated by a multibyte transfer | |
from the processor, and the result after execution of the | |
command may also be a multibyte transfer back to the processor. | |
Because of this multibyte interchange of information between | |
the FDC and the processor, it is convenient to consider each | |
command as consisting of three phases: | |
Command Phase: The FDC receives all information required to | |
perform a particular operation from the processor. | |
Execution Phase: The FDC performs the operation it was | |
instructed to do. | |
Result Phase: After completion of the operation, status | |
and other housekeeping information are made available | |
to the processor. | |
Not all the FDC commands are supported by this emulation. Only the subset | |
of commands required to build an operable CP/M BIOS are supported. They are: | |
Read - Read specified data from the selected FDD. | |
Write - Write specified data to the selected FDD. | |
Seek - Move the R/W head to the specified cylinder on the specified FDD. | |
Specify - Set the characteristics for all the FDDs. | |
Sense Interrupt - Sense change in FDD Ready line or and of Seek/Recalibrate | |
command. | |
Sense Drive - Returns status of all the FDDs. | |
Recalibrate - Move the R/W head to cylinder 0 on the specified FDD. | |
Format Track - Format the current track on the specified FDD. | |
Read ID - Reads the first address mark it finds. | |
Simulated Floppy Disk Drives | |
The units in this device simulate an 8- or 5 1/4- or 3 1/2 inch drives. The | |
drives can emulate SSSD, SSDD, and DSDD. Drives can be attached to files up | |
to 1.44MB in size. Drive configuration is selected when a disk is logged onto | |
the system. An identity sector or identity byte contains information to | |
configure the OS drivers for the type of drive to emulate. | |
uptr->u3 - | |
uptr->u4 - | |
uptr->u5 - | |
uptr->u6 - unit number (0-FDD_NUM) | |
*/ | |
#include "system_defs.h" | |
#define UNIT_V_WPMODE (UNIT_V_UF) /* Write protect */ | |
#define UNIT_WPMODE (1 << UNIT_V_WPMODE) | |
/* master status register definitions */ | |
#define RQM 0x80 /* Request for master */ | |
#define DIO 0x40 /* Data I/O Direction 0=W, 1=R */ | |
#define NDM 0x20 /* Non-DMA mode */ | |
#define CB 0x10 /* FDC busy */ | |
#define D3B 0x08 /* FDD 3 busy */` | |
#define D2B 0x04 /* FDD 2 busy */` | |
#define D1B 0x02 /* FDD 1 busy */` | |
#define D0B 0x01 /* FDD 0 busy */` | |
/* status register 0 definitions */ | |
#define IC 0xC0 /* Interrupt code */ | |
#define IC_NORM 0x00 /* normal completion */ | |
#define IC_ABNORM 0x40 /* abnormal completion */ | |
#define IC_INVC 0x80 /* invalid command */ | |
#define IC_RC 0xC0 /* drive not ready */ | |
#define SE 0x20 /* Seek end */ | |
#define EC 0x10 /* Equipment check */ | |
#define NR 0x08 /* Not ready */ | |
#define HD 0x04 /* Head selected */ | |
#define US 0x03 /* Unit selected */ | |
#define US_0 0x00 /* Unit 0 */ | |
#define US_1 0x01 /* Unit 1 */ | |
#define US_2 0x02 /* Unit 2 */ | |
#define US_3 0x03 /* Unit 3 */ | |
/* status register 1 definitions */ | |
#define EN 0x80 /* End of cylinder */ | |
#define DE 0x20 /* Data error */ | |
#define OR 0x10 /* Overrun */ | |
#define ND 0x04 /* No data */ | |
#define NW 0x02 /* Not writable */ | |
#define MA 0x01 /* Missing address mark */ | |
/* status register 2 definitions */ | |
#define CM 0x40 /* Control mark */ | |
#define DD 0x20 /* Data error in data field */ | |
#define WC 0x10 /* Wrong cylinder */ | |
#define BC 0x02 /* Bad cylinder */ | |
#define MD 0x01 /* Missing address mark in data field */ | |
/* status register 3/fddst definitions */ | |
#define FT 0x80 /* Fault */ | |
#define WP 0x40 /* Write protect */ | |
#define RDY 0x20 /* Ready */ | |
#define T0 0x10 /* Track 0 */ | |
#define TS 0x08 /* Two sided */ | |
//#define HD 0x04 /* Head selected */ | |
//#define US 0x03 /* Unit selected */ | |
/* FDC command definitions */ | |
#define READTRK 0x02 | |
#define SPEC 0x03 | |
#define SENDRV 0x04 | |
#define WRITE 0x05 | |
#define READ 0x06 | |
#define HOME 0x07 | |
#define SENINT 0x08 | |
#define WRITEDEL 0x09 | |
#define READID 0x0A | |
#define READDEL 0x0C | |
#define FMTTRK 0x0D | |
#define SEEK 0x0F | |
#define SCANEQ 0x11 | |
#define SCANLOEQ 0x19 | |
#define SCANHIEQ 0x1D | |
#define FDD_NUM 4 | |
int32 sbc208_devnum = 0; //actual number of 8255 instances + 1 | |
uint16 sbc208_port[4]; //base port registered to each instance | |
/* internal function prototypes */ | |
t_stat isbc208_svc (UNIT *uptr); | |
t_stat isbc208_reset (DEVICE *dptr, uint16 base); | |
void isbc208_reset1 (void); | |
t_stat isbc208_attach (UNIT *uptr, CONST char *cptr); | |
t_stat isbc208_set_mode (UNIT *uptr, int32 val, CONST char *cptr, void *desc); | |
uint8 isbc208_r0(t_bool io, uint8 data); | |
uint8 isbc208_r1(t_bool io, uint8 data); | |
uint8 isbc208_r2(t_bool io, uint8 data); | |
uint8 isbc208_r3(t_bool io, uint8 data); | |
uint8 isbc208_r4(t_bool io, uint8 data); | |
uint8 isbc208_r5(t_bool io, uint8 data); | |
uint8 isbc208_r6(t_bool io, uint8 data); | |
uint8 isbc208_r7(t_bool io, uint8 data); | |
uint8 isbc208_r8(t_bool io, uint8 data); | |
uint8 isbc208_r9(t_bool io, uint8 data); | |
uint8 isbc208_rA(t_bool io, uint8 data); | |
uint8 isbc208_rB(t_bool io, uint8 data); | |
uint8 isbc208_rC(t_bool io, uint8 data); | |
uint8 isbc208_rD(t_bool io, uint8 data); | |
uint8 isbc208_rE(t_bool io, uint8 data); | |
uint8 isbc208_rF(t_bool io, uint8 data); | |
uint8 isbc208_r10(t_bool io, uint8 data); | |
uint8 isbc208_r11(t_bool io, uint8 data); | |
uint8 isbc208_r12(t_bool io, uint8 data); | |
uint8 isbc208_r13(t_bool io, uint8 data); | |
uint8 isbc208_r14(t_bool io, uint8 data); | |
uint8 isbc208_r15(t_bool io, uint8 data); | |
/* external function prototypes */ | |
extern void set_irq(int32 int_num); | |
extern void clr_irq(int32 int_num); | |
extern uint16 reg_dev(uint8 (*routine)(t_bool, uint8), uint16, uint8); | |
extern void multibus_put_mbyte(uint16 addr, uint8 val); | |
extern uint8 multibus_get_mbyte(uint16 addr); | |
/* 8237 physical register definitions */ | |
uint16 i8237_r0; // 8237 ch 0 address register | |
uint16 i8237_r1; // 8237 ch 0 count register | |
uint16 i8237_r2; // 8237 ch 1 address register | |
uint16 i8237_r3; // 8237 ch 1 count register | |
uint16 i8237_r4; // 8237 ch 2 address register | |
uint16 i8237_r5; // 8237 ch 2 count register | |
uint16 i8237_r6; // 8237 ch 3 address register | |
uint16 i8237_r7; // 8237 ch 3 count register | |
uint8 i8237_r8; // 8237 status register | |
uint8 i8237_r9; // 8237 command register | |
uint8 i8237_rA; // 8237 mode register | |
uint8 i8237_rB; // 8237 mask register | |
uint8 i8237_rC; // 8237 request register | |
uint8 i8237_rD; // 8237 first/last ff | |
uint8 i8237_rE; // 8237 | |
uint8 i8237_rF; // 8237 | |
/* 8272 physical register definitions */ | |
/* 8272 command register stack*/ | |
uint8 i8272_w0; // MT+MFM+SK+command | |
uint8 i8272_w1; // HDS [HDS=H << 2] + DS1 + DS0 | |
uint8 i8272_w2; // cylinder # (0-XX) | |
uint8 i8272_w3; // head # (0 or 1) | |
uint8 i8272_w4; // sector # (1-XX) | |
uint8 i8272_w5; // number of bytes (128 << N) | |
uint8 i8272_w6; // End of track (last sector # on cylinder) | |
uint8 i8272_w7; // Gap length | |
uint8 i8272_w8; // Data length (when N=0, size to read or write) | |
/* 8272 status register stack */ | |
uint8 i8272_msr; // main status | |
uint8 i8272_r0; // ST 0 | |
uint8 i8272_r1; // ST 1 | |
uint8 i8272_r2; // ST 2 | |
uint8 i8272_r3; // ST 3 | |
/* iSBC-208 physical register definitions */ | |
uint16 isbc208_sr; // isbc-208 segment register | |
uint8 isbc208_i; // iSBC-208 interrupt register | |
uint8 isbc208_a; // iSBC-208 auxillary port register | |
/* data obtained from analyzing command registers/attached file length */ | |
int32 wsp = 0, rsp = 0; // indexes to write and read stacks (8272 data) | |
int32 cyl; // current cylinder | |
int32 hed; // current head [ h << 2] | |
int32 h; // current head | |
int32 sec; // current sector | |
int32 drv; // current drive | |
uint8 cmd, pcmd; // current command | |
int32 secn; // N 0-128, 1-256, etc | |
int32 spt; // sectors per track | |
int32 ssize; // sector size (128 << N) | |
uint8 *isbc208_buf[FDD_NUM] = { /* FDD buffer pointers */ | |
NULL, | |
NULL, | |
NULL, | |
NULL | |
}; | |
int32 fddst[FDD_NUM] = { // in ST3 format | |
0, // status of FDD 0 | |
0, // status of FDD 1 | |
0, // status of FDD 2 | |
0 // status of FDD 3 | |
}; | |
int8 maxcyl[FDD_NUM] = { | |
0, // last cylinder + 1 of FDD 0 | |
0, // last cylinder + 1 of FDD 1 | |
0, // last cylinder + 1 of FDD 2 | |
0 // last cylinder + 1 of FDD 3 | |
}; | |
/* isbc208 Standard SIMH Device Data Structures - 4 units */ | |
UNIT isbc208_unit[] = { | |
{ UDATA (&isbc208_svc, UNIT_ATTABLE+UNIT_DISABLE, 0), 20 }, | |
{ UDATA (&isbc208_svc, UNIT_ATTABLE+UNIT_DISABLE, 0), 20 }, | |
{ UDATA (&isbc208_svc, UNIT_ATTABLE+UNIT_DISABLE, 0), 20 }, | |
{ UDATA (&isbc208_svc, UNIT_ATTABLE+UNIT_DISABLE, 0), 20 } | |
}; | |
REG isbc208_reg[] = { | |
{ HRDATA (CH0ADR, i8237_r0, 16) }, | |
{ HRDATA (CH0CNT, i8237_r1, 16) }, | |
{ HRDATA (CH1ADR, i8237_r2, 16) }, | |
{ HRDATA (CH1CNT, i8237_r3, 16) }, | |
{ HRDATA (CH2ADR, i8237_r4, 16) }, | |
{ HRDATA (CH2CNT, i8237_r5, 16) }, | |
{ HRDATA (CH3ADR, i8237_r6, 16) }, | |
{ HRDATA (CH3CNT, i8237_r7, 16) }, | |
{ HRDATA (STAT37, i8237_r8, 8) }, | |
{ HRDATA (CMD37, i8237_r9, 8) }, | |
{ HRDATA (MODE, i8237_rA, 8) }, | |
{ HRDATA (MASK, i8237_rB, 8) }, | |
{ HRDATA (REQ, i8237_rC, 8) }, | |
{ HRDATA (FF, i8237_rD, 8) }, | |
{ HRDATA (STAT72, i8272_msr, 8) }, | |
{ HRDATA (STAT720, i8272_r0, 8) }, | |
{ HRDATA (STAT721, i8272_r1, 8) }, | |
{ HRDATA (STAT722, i8272_r2, 8) }, | |
{ HRDATA (STAT723, i8272_r3, 8) }, | |
{ HRDATA (CMD720, i8272_w0, 8) }, | |
{ HRDATA (CMD721, i8272_w1, 8) }, | |
{ HRDATA (CMD722, i8272_w2, 8) }, | |
{ HRDATA (CMD723, i8272_w3, 8) }, | |
{ HRDATA (CMD724, i8272_w4, 8) }, | |
{ HRDATA (CMD725, i8272_w5, 8) }, | |
{ HRDATA (CMD726, i8272_w6, 8) }, | |
{ HRDATA (CMD727, i8272_w7, 8) }, | |
{ HRDATA (CMD728, i8272_w8, 8) }, | |
{ HRDATA (FDD0, fddst[0], 8) }, | |
{ HRDATA (FDD1, fddst[1], 8) }, | |
{ HRDATA (FDD2, fddst[2], 8) }, | |
{ HRDATA (FDD3, fddst[3], 8) }, | |
{ HRDATA (SEGREG, isbc208_sr, 8) }, | |
{ HRDATA (AUX, isbc208_a, 8) }, | |
{ HRDATA (INT, isbc208_i, 8) }, | |
{ NULL } | |
}; | |
MTAB isbc208_mod[] = { | |
{ UNIT_WPMODE, 0, "RW", "RW", &isbc208_set_mode }, | |
{ UNIT_WPMODE, UNIT_WPMODE, "WP", "WP", &isbc208_set_mode }, | |
{ 0 } | |
}; | |
DEBTAB isbc208_debug[] = { | |
{ "ALL", DEBUG_all }, | |
{ "FLOW", DEBUG_flow }, | |
{ "READ", DEBUG_read }, | |
{ "WRITE", DEBUG_write }, | |
{ "LEV1", DEBUG_level1 }, | |
{ "LEV2", DEBUG_level2 }, | |
{ "REG", DEBUG_reg }, | |
{ NULL } | |
}; | |
DEVICE isbc208_dev = { | |
"SBC208", //name | |
isbc208_unit, //units | |
isbc208_reg, //registers | |
isbc208_mod, //modifiers | |
FDD_NUM, //numunits | |
16, //aradix | |
32, //awidth | |
1, //aincr | |
16, //dradix | |
8, //dwidth | |
NULL, //examine | |
NULL, //deposit | |
// &isbc208_reset, //deposit | |
NULL, //deposit | |
NULL, //boot | |
&isbc208_attach, //attach | |
NULL, //detach | |
NULL, //ctxt | |
DEV_DEBUG+DEV_DISABLE+DEV_DIS, //flags | |
// 0, //dctrl | |
DEBUG_flow + DEBUG_read + DEBUG_write, //dctrl | |
isbc208_debug, //debflags | |
NULL, //msize | |
NULL //lname | |
}; | |
/* Service routines to handle simulator functions */ | |
/* service routine - actually does the simulated disk I/O */ | |
t_stat isbc208_svc (UNIT *uptr) | |
{ | |
uint32 i; | |
int32 imgadr, data; | |
int c; | |
int32 bpt, bpc; | |
FILE *fp; | |
if ((i8272_msr & CB) && cmd && (uptr->u6 == drv)) { /* execution phase */ | |
sim_debug (DEBUG_flow, &isbc208_dev, "208_svc: Entered execution phase\n"); | |
switch (cmd) { | |
case READ: /* 0x06 */ | |
// sim_printf("READ-e: fddst=%02X", fddst[uptr->u6]); | |
h = i8272_w3; // h = 0 or 1 | |
hed = i8272_w3 << 2; // hed = 0 or 4 [h << 2] | |
sec = i8272_w4; // sector number (1-XX) | |
secn = i8272_w5; // N (0-5) | |
spt = i8272_w6; // sectors/track | |
ssize = 128 << secn; // size of sector (bytes) | |
bpt = ssize * spt; // bytes/track | |
bpc = bpt * 2; // bytes/cylinder | |
// sim_printf(" d=%d h=%d c=%d s=%d\n", drv, h, cyl, sec); | |
sim_debug (DEBUG_flow, &isbc208_dev, | |
"208_svc: FDC read: h=%d, hed=%d, sec=%d, secn=%d, spt=%d, ssize=%04X, bpt=%04X, bpc=%04X\n", | |
h, hed, sec, secn, spt, ssize, bpt, bpc); | |
sim_debug (DEBUG_flow, &isbc208_dev, | |
"208_svc: FDC read: d=%d h=%d c=%d s=%d N=%d spt=%d fddst=%02X\n", | |
drv, h, cyl, sec, secn, spt, fddst[uptr->u6]); | |
sim_debug (DEBUG_read, &isbc208_dev, "208_svc: FDC read of d=%d h=%d c=%d s=%d\n", | |
drv, h, cyl, sec); | |
if ((fddst[uptr->u6] & RDY) == 0) { // drive not ready | |
i8272_r0 = IC_ABNORM + NR + hed + drv; /* command done - Not ready error*/ | |
i8272_r3 = fddst[uptr->u6]; | |
i8272_msr |= (RQM + DIO + CB); /* enter result phase */ | |
sim_debug (DEBUG_flow, &isbc208_dev, "208_svc: FDC read: Not Ready\n"); | |
} else { // get image addr for this d, h, c, s | |
imgadr = (cyl * bpc) + (h * bpt) + ((sec - 1) * ssize); | |
sim_debug (DEBUG_read, &isbc208_dev, | |
"208_svc: FDC read: DMA addr=%04X cnt=%04X imgadr=%04X\n", | |
i8237_r0, i8237_r1, imgadr); | |
for (i=0; i<=i8237_r1; i++) { /* copy selected sector to memory */ | |
data = *(isbc208_buf[uptr->u6] + (imgadr + i)); | |
multibus_put_mbyte(i8237_r0 + i, data); | |
} | |
//*** need to step return results IAW table 3-11 in 143078-001 | |
i8272_w4 = ++sec; /* next sector */ | |
i8272_r0 = hed + drv; /* command done - no error */ | |
i8272_r3 = fddst[uptr->u6]; | |
} | |
i8272_r1 = 0; | |
i8272_r2 = 0; | |
i8272_w2 = cyl; /* generate a current address mark */ | |
i8272_w3 = h; | |
if (i8272_w4 > i8272_w6) { // beyond last sector of track? | |
i8272_w4 = 1; // yes, set to sector 1; | |
if (h) { // on head one? | |
i8272_w2++; // yes, step cylinder | |
h = 0; // back to head 0 | |
} | |
} | |
i8272_w5 = secn; | |
i8272_msr |= (RQM + DIO + CB); /* enter result phase */ | |
rsp = wsp = 0; /* reset indexes */ | |
set_irq(SBC208_INT); /* set interrupt */ | |
// sim_printf("READ-x: fddst=%02X\n", fddst[uptr->u6]); | |
break; | |
case WRITE: /* 0x05 */ | |
// sim_printf("WRITE-e: fddst=%02X\n", fddst[uptr->u6]); | |
h = i8272_w3; // h = 0 or 1 | |
hed = i8272_w3 << 2; // hed = 0 or 4 [h << 2] | |
sec = i8272_w4; // sector number (1-XX) | |
secn = i8272_w5; // N (0-5) | |
spt = i8272_w6; // sectors/track | |
ssize = 128 << secn; // size of sector (bytes) | |
bpt = ssize * spt; // bytes/track | |
bpc = bpt * 2; // bytes/cylinder | |
sim_debug (DEBUG_flow, &isbc208_dev, | |
"208_svc: FDC write: hed=%d, sec=%d, secn=%d, spt=%d, ssize=%04X, bpt=%04X, bpc=%04X\n", | |
hed, sec, secn, spt, ssize, bpt, bpc); | |
sim_debug (DEBUG_flow, &isbc208_dev, | |
"208_svc: FDC write: d=%d h=%d c=%d s=%d N=%d spt=%d fddst=%02X\n", | |
drv, h, cyl, sec, secn, spt, fddst[uptr->u6]); | |
sim_debug (DEBUG_write, &isbc208_dev, "208_svc: FDC write of d=%d h=%d c=%d s=%d\n", | |
drv, h, cyl, sec); | |
i8272_r1 = 0; // clear ST1 | |
i8272_r2 = 0; // clear ST2 | |
if ((fddst[uptr->u6] & RDY) == 0) { | |
i8272_r0 = IC_ABNORM + NR + hed + drv; /* Not ready error*/ | |
i8272_r3 = fddst[uptr->u6]; | |
i8272_msr |= (RQM + DIO + CB); /* enter result phase */ | |
sim_debug (DEBUG_flow, &isbc208_dev, "208_svc: FDC write: Not Ready\n"); | |
// } else if (fddst[uptr->u6] & WP) { | |
// i8272_r0 = IC_ABNORM + hed + drv; /* write protect error*/ | |
// i8272_r1 = NW; // set not writable in ST1 | |
// i8272_r3 = fddst[uptr->u6] + WP; | |
// i8272_msr |= (RQM + DIO + CB); /* enter result phase */ | |
// sim_printf("\nWrite Protected fddst[%d]=%02X\n", uptr->u6, fddst[uptr->u6]); | |
// if (isbc208_dev.dctrl & DEBUG_flow) | |
// sim_printf("208_svc: FDC write: Write Protected\n"); | |
} else { // get image addr for this d, h, c, s | |
imgadr = (cyl * bpc) + (h * bpt) + ((sec - 1) * ssize); | |
sim_debug (DEBUG_write, &isbc208_dev, | |
"208_svc: FDC write: DMA adr=%04X cnt=%04X imgadr=%04X\n", | |
i8237_r0, i8237_r1, imgadr); | |
for (i=0; i<=i8237_r1; i++) { /* copy selected memory to image */ | |
data = multibus_get_mbyte(i8237_r0 + i); | |
*(isbc208_buf[uptr->u6] + (imgadr + i)) = data; | |
} | |
//*** quick fix. Needs more thought! | |
fp = fopen(uptr->filename, "wb"); // write out modified image | |
for (i=0; i<uptr->capac; i++) { | |
c = *(isbc208_buf[uptr->u6] + i) & 0xFF; | |
fputc(c, fp); | |
} | |
fclose(fp); | |
//*** need to step return results IAW table 3-11 in 143078-001 | |
i8272_w2 = cyl; /* generate a current address mark */ | |
i8272_w3 = hed >> 2; | |
i8272_w4 = ++sec; /* next sector */ | |
i8272_w5 = secn; | |
i8272_r0 = hed + drv; /* command done - no error */ | |
i8272_r3 = fddst[uptr->u6]; | |
i8272_msr |= (RQM + DIO + CB); /* enter result phase */ | |
} | |
rsp = wsp = 0; /* reset indexes */ | |
set_irq(SBC208_INT); /* set interrupt */ | |
// sim_printf("WRITE-x: fddst=%02X\n", fddst[uptr->u6]); | |
break; | |
case FMTTRK: /* 0x0D */ | |
if ((fddst[uptr->u6] & RDY) == 0) { | |
i8272_r0 = IC_ABNORM + NR + hed + drv; /* Not ready error*/ | |
i8272_msr |= (RQM + DIO + CB); /* enter result phase */ | |
sim_debug (DEBUG_flow, &isbc208_dev, "208_svc: Not Ready\n"); | |
} else if (fddst[uptr->u6] & WP) { | |
i8272_r0 = IC_ABNORM + hed + drv; /* write protect error*/ | |
i8272_r3 = fddst[uptr->u6] + WP; | |
i8272_msr |= (RQM + DIO + CB); /* enter result phase */ | |
sim_debug (DEBUG_flow, &isbc208_dev, "208_svc: Write Protected\n"); | |
} else { | |
; /* do nothing for now */ | |
i8272_msr |= (RQM + DIO + CB); /* enter result phase */ | |
} | |
rsp = wsp = 0; /* reset indexes */ | |
set_irq(SBC208_INT); /* set interrupt */ | |
break; | |
case SENINT: /* 0x08 */ | |
i8272_msr |= (RQM + DIO + CB); /* enter result phase */ | |
i8272_r0 = hed + drv; /* command done - no error */ | |
i8272_r1 = 0; | |
i8272_r2 = 0; | |
rsp = wsp = 0; /* reset indexes */ | |
clr_irq(SBC208_INT); /* clear interrupt */ | |
break; | |
case SENDRV: /* 0x04 */ | |
sim_debug (DEBUG_flow, &isbc208_dev, "208_svc: FDC sense drive: d=%d fddst=%02X\n", | |
drv, fddst[uptr->u6]); | |
i8272_msr |= (RQM + DIO + CB); /* enter result phase */ | |
i8272_r0 = hed + drv; /* command done - no error */ | |
i8272_r1 = 0; | |
i8272_r2 = 0; | |
i8272_r3 = fddst[drv]; /* drv status */ | |
rsp = wsp = 0; /* reset indexes */ | |
break; | |
case HOME: /* 0x07 */ | |
// sim_printf("HOME-e: fddst=%02X\n", fddst[uptr->u6]); | |
sim_debug (DEBUG_flow, &isbc208_dev, "208_svc: FDC home: d=%d fddst=%02X\n", | |
drv, fddst[uptr->u6]); | |
if ((fddst[uptr->u6] & RDY) == 0) { | |
i8272_r0 = IC_ABNORM + NR + hed + drv; /* Not ready error*/ | |
i8272_r3 = fddst[uptr->u6]; | |
sim_debug (DEBUG_flow, &isbc208_dev, "208_svc: Not Ready\n"); | |
} else { | |
cyl = 0; /* now on cylinder 0 */ | |
fddst[drv] |= T0; /* set status flag */ | |
i8272_r0 = SE + hed + drv; /* seek end - no error */ | |
} | |
i8272_r1 = 0; | |
i8272_r2 = 0; | |
i8272_msr &= ~(RQM + DIO + CB + hed + drv); /* execution phase done*/ | |
i8272_msr |= RQM; /* enter COMMAND phase */ | |
rsp = wsp = 0; /* reset indexes */ | |
set_irq(SBC208_INT); /* set interrupt */ | |
// sim_printf("HOME-x: fddst=%02X\n", fddst[uptr->u6]); | |
break; | |
case SPEC: /* 0x03 */ | |
fddst[0] |= TS; //*** bad, bad, bad! | |
fddst[1] |= TS; | |
fddst[2] |= TS; | |
fddst[3] |= TS; | |
// sim_printf("SPEC-e: fddst[%d]=%02X\n", uptr->u6, fddst[uptr->u6]); | |
sim_debug (DEBUG_flow, &isbc208_dev, | |
"208_svc: FDC specify: SRT=%d ms HUT=%d ms HLT=%d ms \n", | |
16 - (drv >> 4), 16 * (drv & 0x0f), i8272_w2 & 0xfe); | |
i8272_r0 = hed + drv; /* command done - no error */ | |
i8272_r1 = 0; | |
i8272_r2 = 0; | |
// i8272_msr &= ~(RQM + DIO + CB); /* execution phase done*/ | |
i8272_msr = 0; // force 0 for now, where does 0x07 come from? | |
i8272_msr |= RQM; /* enter command phase */ | |
rsp = wsp = 0; /* reset indexes */ | |
// sim_printf("SPEC-x: fddst[%d]=%02X\n", uptr->u6, fddst[uptr->u6]); | |
break; | |
case READID: /* 0x0A */ | |
if ((fddst[uptr->u6] & RDY) == 0) { | |
i8272_r0 = IC_RC + NR + hed + drv; /* Not ready error*/ | |
i8272_r3 = fddst[uptr->u6]; | |
sim_debug (DEBUG_flow, &isbc208_dev, "208_svc: Not Ready\n"); | |
} else { | |
i8272_w2 = cyl; /* generate a valid address mark */ | |
i8272_w3 = hed >> 2; | |
i8272_w4 = 1; /* always sector 1 */ | |
i8272_w5 = secn; | |
i8272_r0 = hed + drv; /* command done - no error */ | |
i8272_msr &= ~(RQM + DIO + CB); /* execution phase done*/ | |
i8272_msr |= RQM; /* enter command phase */ | |
} | |
i8272_r1 = 0; | |
i8272_r2 = 0; | |
rsp = wsp = 0; /* reset indexes */ | |
break; | |
case SEEK: /* 0x0F */ | |
// sim_printf("SEEK-e: fddst=%02X\n", fddst[uptr->u6]); | |
sim_debug (DEBUG_flow, &isbc208_dev, "208_svc: FDC seek: d=%d c=%d fddst=%02X\n", | |
drv, i8272_w2, fddst[uptr->u6]); | |
if ((fddst[uptr->u6] & RDY) == 0) { /* Not ready? */ | |
i8272_r0 = IC_ABNORM + NR + hed + drv; /* error*/ | |
i8272_r3 = fddst[uptr->u6]; | |
sim_debug (DEBUG_flow, &isbc208_dev, "208_svc: FDC seek: Not Ready\n"); | |
} else if (i8272_w2 >= maxcyl[uptr->u6]) { | |
i8272_r0 = IC_ABNORM + RDY + hed + drv; /* seek error*/ | |
sim_debug (DEBUG_flow, &isbc208_dev, "208_svc: FDC seek: Invalid Cylinder %d\n", i8272_w2); | |
} else { | |
i8272_r0 |= SE + hed + drv; /* command done - no error */ | |
cyl = i8272_w2; /* new cylinder number */ | |
if (cyl == 0) { /* if cyl 0, set flag */ | |
fddst[drv] |= T0; /* set T0 status flag */ | |
i8272_r3 |= T0; | |
} else { | |
fddst[drv] &= ~T0; /* clear T0 status flag */ | |
i8272_r3 &= ~T0; | |
} | |
} | |
i8272_r1 = 0; | |
i8272_r2 = 0; | |
i8272_msr &= ~(RQM + DIO + CB + hed + drv); /* execution phase done*/ | |
i8272_msr |= RQM; /* enter command phase */ | |
rsp = wsp = 0; /* reset indexes */ | |
// set_irq(SBC208_INT); /* set interrupt */ | |
// sim_printf("SEEK-x: fddst=%02X\n", fddst[uptr->u6]); | |
break; | |
default: | |
i8272_msr &= ~(RQM + DIO + CB); /* execution phase done*/ | |
i8272_msr |= RQM; /* enter command phase */ | |
i8272_r0 = IC_INVC + hed + drv; /* set bad command error */ | |
i8272_r1 = 0; | |
i8272_r2 = 0; | |
rsp = wsp = 0; /* reset indexes */ | |
break; | |
} | |
pcmd = cmd; /* save for result phase */ | |
cmd = 0; /* reset command */ | |
sim_debug (DEBUG_flow, &isbc208_dev, | |
"208_svc: Exit: msr=%02X ST0=%02X ST1=%02X ST2=%02X ST3=%02X\n", | |
i8272_msr, i8272_r0, i8272_r1, i8272_r2, i8272_r3); | |
} | |
sim_activate (&isbc208_unit[uptr->u6], isbc208_unit[uptr->u6].wait); | |
return SCPE_OK; | |
} | |
/* Reset routine */ | |
t_stat isbc208_reset (DEVICE *dptr, uint16 base) | |
{ | |
if (sbc208_devnum > SBC208_NUM) { | |
sim_printf("sbc208_reset: too many devices!\n"); | |
return SCPE_MEM; | |
} | |
if (SBC202_NUM) { | |
sim_printf(" SBC208-%d: Hardware Reset\n", sbc208_devnum); | |
sim_printf(" SBC208-%d: Registered at %04X\n", sbc208_devnum, base); | |
sbc208_port[sbc208_devnum] = reg_dev(isbc208_r0, SBC208_BASE + 0, sbc208_devnum); | |
reg_dev(isbc208_r1, SBC208_BASE + 1, sbc208_devnum); | |
reg_dev(isbc208_r2, SBC208_BASE + 2, sbc208_devnum); | |
reg_dev(isbc208_r3, SBC208_BASE + 3, sbc208_devnum); | |
reg_dev(isbc208_r4, SBC208_BASE + 4, sbc208_devnum); | |
reg_dev(isbc208_r5, SBC208_BASE + 5, sbc208_devnum); | |
reg_dev(isbc208_r6, SBC208_BASE + 6, sbc208_devnum); | |
reg_dev(isbc208_r7, SBC208_BASE + 7, sbc208_devnum); | |
reg_dev(isbc208_r8, SBC208_BASE + 8, sbc208_devnum); | |
reg_dev(isbc208_r9, SBC208_BASE + 9, sbc208_devnum); | |
reg_dev(isbc208_rA, SBC208_BASE + 10, sbc208_devnum); | |
reg_dev(isbc208_rB, SBC208_BASE + 11, sbc208_devnum); | |
reg_dev(isbc208_rC, SBC208_BASE + 12, sbc208_devnum); | |
reg_dev(isbc208_rD, SBC208_BASE + 13, sbc208_devnum); | |
reg_dev(isbc208_rE, SBC208_BASE + 14, sbc208_devnum); | |
reg_dev(isbc208_rF, SBC208_BASE + 15, sbc208_devnum); | |
reg_dev(isbc208_r10, SBC208_BASE + 16, sbc208_devnum); | |
reg_dev(isbc208_r11, SBC208_BASE + 17, sbc208_devnum); | |
reg_dev(isbc208_r12, SBC208_BASE + 18, sbc208_devnum); | |
reg_dev(isbc208_r13, SBC208_BASE + 19, sbc208_devnum); | |
reg_dev(isbc208_r14, SBC208_BASE + 20, sbc208_devnum); | |
reg_dev(isbc208_r15, SBC208_BASE + 21, sbc208_devnum); | |
if ((isbc208_dev.flags & DEV_DIS) == 0) | |
isbc208_reset1(); | |
sbc208_devnum++; | |
} else { | |
sim_printf(" No isbc208 installed\n"); | |
} | |
return SCPE_OK; | |
} | |
void isbc208_reset1 (void) | |
{ | |
int32 i; | |
UNIT *uptr; | |
static int flag = 1; | |
if (flag) sim_printf("iSBC 208: Initializing\n"); | |
for (i = 0; i < FDD_NUM; i++) { /* handle all units */ | |
uptr = isbc208_dev.units + i; | |
if (uptr->capac == 0) { /* if not configured */ | |
// sim_printf(" SBC208%d: Not configured\n", i); | |
// if (flag) { | |
// sim_printf(" ALL: \"set isbc208 en\"\n"); | |
// sim_printf(" EPROM: \"att isbc2080 <filename>\"\n"); | |
// flag = 0; | |
// } | |
uptr->capac = 0; /* initialize unit */ | |
uptr->u3 = 0; | |
uptr->u4 = 0; | |
uptr->u5 = 0; | |
uptr->u6 = i; /* unit number - only set here! */ | |
fddst[i] = WP + T0 + i; /* initial drive status */ | |
uptr->flags |= UNIT_WPMODE; /* set WP in unit flags */ | |
sim_activate (&isbc208_unit[uptr->u6], isbc208_unit[uptr->u6].wait); | |
} else { | |
fddst[i] = RDY + WP + T0 + i; /* initial attach drive status */ | |
// sim_printf(" SBC208%d: Configured, Attached to %s\n", i, uptr->filename); | |
} | |
} | |
i8237_r8 = 0; /* status */ | |
i8237_r9 = 0; /* command */ | |
i8237_rB = 0x0F; /* mask */ | |
i8237_rC = 0; /* request */ | |
i8237_rD = 0; /* first/last FF */ | |
i8272_msr = RQM; /* 8272 ready for start of command */ | |
rsp = wsp = 0; /* reset indexes */ | |
cmd = 0; /* clear command */ | |
sim_printf(" SBC208-%d: Software Reset\n", sbc208_devnum); | |
if (flag) { | |
sim_printf(" 8237 Reset\n"); | |
sim_printf(" 8272 Reset\n"); | |
} | |
flag = 0; | |
} | |
/* isbc208 attach - attach an .IMG file to a FDD */ | |
t_stat isbc208_attach (UNIT *uptr, CONST char *cptr) | |
{ | |
t_stat r; | |
FILE *fp; | |
int32 i, c = 0; | |
long flen; | |
sim_debug (DEBUG_flow, &isbc208_dev, " isbc208_attach: Entered with cptr=%s\n", cptr); | |
if ((r = attach_unit (uptr, cptr)) != SCPE_OK) { | |
sim_printf(" isbc208_attach: Attach error\n"); | |
return r; | |
} | |
fp = fopen(uptr->filename, "rb"); | |
if (fp == NULL) { | |
sim_printf(" Unable to open disk img file %s\n", uptr->filename); | |
sim_printf(" No disk image loaded!!!\n"); | |
} else { | |
sim_printf("iSBC 208: Attach\n"); | |
fseek(fp, 0, SEEK_END); /* size disk image */ | |
flen = ftell(fp); | |
fseek(fp, 0, SEEK_SET); | |
if (flen == -1) { | |
sim_printf(" isbc208_attach: File error\n"); | |
return SCPE_IOERR; | |
} | |
if (isbc208_buf[uptr->u6] == NULL) { /* no buffer allocated */ | |
isbc208_buf[uptr->u6] = (uint8 *)malloc(flen); | |
if (isbc208_buf[uptr->u6] == NULL) { | |
sim_printf(" iSBC208_attach: Malloc error\n"); | |
return SCPE_MEM; | |
} | |
} | |
uptr->capac = flen; | |
i = 0; | |
c = fgetc(fp); // copy disk image into buffer | |
while (c != EOF) { | |
*(isbc208_buf[uptr->u6] + i++) = c & 0xFF; | |
c = fgetc(fp); | |
} | |
fclose(fp); | |
fddst[uptr->u6] |= RDY; /* set unit ready */ | |
if (flen == 368640) { /* 5" 360K DSDD */ | |
maxcyl[uptr->u6] = 40; | |
fddst[uptr->u6] |= TS; // two sided | |
} | |
else if (flen == 737280) { /* 5" 720K DSQD / 3.5" 720K DSDD */ | |
maxcyl[uptr->u6] = 80; | |
fddst[uptr->u6] |= TS; // two sided | |
} | |
else if (flen == 1228800) { /* 5" 1.2M DSHD */ | |
maxcyl[uptr->u6] = 80; | |
fddst[uptr->u6] |= TS; // two sided | |
} | |
else if (flen == 1474560) { /* 3.5" 1.44M DSHD */ | |
maxcyl[uptr->u6] = 80; | |
fddst[uptr->u6] |= TS; // two sided | |
} | |
sim_printf(" Drive-%d: %d bytes of disk image %s loaded, fddst=%02X\n", | |
uptr->u6, i, uptr->filename, fddst[uptr->u6]); | |
} | |
sim_debug (DEBUG_flow, &isbc208_dev, " iSBC208_attach: Done\n"); | |
return SCPE_OK; | |
} | |
/* isbc208 set mode = 8- or 16-bit data bus */ | |
/* always 8-bit mode for current simulators */ | |
t_stat isbc208_set_mode (UNIT *uptr, int32 val, CONST char *cptr, void *desc) | |
{ | |
sim_debug (DEBUG_flow, &isbc208_dev, " isbc208_set_mode: Entered with val=%08XH uptr->flags=%08X\n", | |
val, uptr->flags); | |
if (val & UNIT_WPMODE) { /* write protect */ | |
fddst[uptr->u6] |= WP; | |
uptr->flags |= val; | |
} else { /* read write */ | |
fddst[uptr->u6] &= ~WP; | |
uptr->flags &= ~val; | |
} | |
// sim_printf("fddst[%d]=%02XH uptr->flags=%08X\n", uptr->u6, fddst[uptr->u6], uptr->flags); | |
sim_debug (DEBUG_flow, &isbc208_dev, " isbc208_set_mode: Done\n"); | |
return SCPE_OK; | |
} | |
/* I/O instruction handlers, called from the CPU module when an | |
IN or OUT instruction is issued. | |
Each function is passed an 'io' flag, where 0 means a read from | |
the port, and 1 means a write to the port. On input, the actual | |
input is passed as the return value, on output, 'data' is written | |
to the device. | |
*/ | |
uint8 isbc208_r0(t_bool io, uint8 data) | |
{ | |
if (io == 0) { /* read current address CH 0 */ | |
if (i8237_rD) { /* high byte */ | |
i8237_rD = 0; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r0(H) read as %04X\n", i8237_r0); | |
return (i8237_r0 >> 8); | |
} else { /* low byte */ | |
i8237_rD++; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r0(L) read as %04X\n", i8237_r0); | |
return (i8237_r0 & 0xFF); | |
} | |
} else { /* write base & current address CH 0 */ | |
if (i8237_rD) { /* high byte */ | |
i8237_rD = 0; | |
i8237_r0 |= (data << 8); | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r0(H) set to %04X\n", i8237_r0); | |
} else { /* low byte */ | |
i8237_rD++; | |
i8237_r0 = data & 0xFF; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r0(L) set to %04X\n", i8237_r0); | |
} | |
return 0; | |
} | |
} | |
uint8 isbc208_r1(t_bool io, uint8 data) | |
{ | |
if (io == 0) { /* read current word count CH 0 */ | |
if (i8237_rD) { /* high byte */ | |
i8237_rD = 0; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r1(H) read as %04X\n", i8237_r1); | |
return (i8237_r1 >> 8); | |
} else { /* low byte */ | |
i8237_rD++; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r1(L) read as %04X\n", i8237_r1); | |
return (i8237_r1 & 0xFF); | |
} | |
} else { /* write base & current address CH 0 */ | |
if (i8237_rD) { /* high byte */ | |
i8237_rD = 0; | |
i8237_r1 |= (data << 8); | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r1(H) set to %04X\n", i8237_r1); | |
} else { /* low byte */ | |
i8237_rD++; | |
i8237_r1 = data & 0xFF; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r1(L) set to %04X\n", i8237_r1); | |
} | |
return 0; | |
} | |
} | |
uint8 isbc208_r2(t_bool io, uint8 data) | |
{ | |
if (io == 0) { /* read current address CH 1 */ | |
if (i8237_rD) { /* high byte */ | |
i8237_rD = 0; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r2(H) read as %04X\n", i8237_r2); | |
return (i8237_r2 >> 8); | |
} else { /* low byte */ | |
i8237_rD++; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r2(L) read as %04X\n", i8237_r2); | |
return (i8237_r2 & 0xFF); | |
} | |
} else { /* write base & current address CH 1 */ | |
if (i8237_rD) { /* high byte */ | |
i8237_rD = 0; | |
i8237_r2 |= (data << 8); | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r2(H) set to %04X\n", i8237_r2); | |
} else { /* low byte */ | |
i8237_rD++; | |
i8237_r2 = data & 0xFF; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r2(L) set to %04X\n", i8237_r2); | |
} | |
return 0; | |
} | |
} | |
uint8 isbc208_r3(t_bool io, uint8 data) | |
{ | |
if (io == 0) { /* read current word count CH 1 */ | |
if (i8237_rD) { /* high byte */ | |
i8237_rD = 0; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r3(H) read as %04X\n", i8237_r3); | |
return (i8237_r3 >> 8); | |
} else { /* low byte */ | |
i8237_rD++; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r3(L) read as %04X\n", i8237_r3); | |
return (i8237_r3 & 0xFF); | |
} | |
} else { /* write base & current address CH 1 */ | |
if (i8237_rD) { /* high byte */ | |
i8237_rD = 0; | |
i8237_r3 |= (data << 8); | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r3(H) set to %04X\n", i8237_r3); | |
} else { /* low byte */ | |
i8237_rD++; | |
i8237_r3 = data & 0xFF; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r3(L) set to %04X\n", i8237_r3); | |
} | |
return 0; | |
} | |
} | |
uint8 isbc208_r4(t_bool io, uint8 data) | |
{ | |
if (io == 0) { /* read current address CH 2 */ | |
if (i8237_rD) { /* high byte */ | |
i8237_rD = 0; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r4(H) read as %04X\n", i8237_r4); | |
return (i8237_r4 >> 8); | |
} else { /* low byte */ | |
i8237_rD++; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r4(L) read as %04X\n", i8237_r4); | |
return (i8237_r4 & 0xFF); | |
} | |
} else { /* write base & current address CH 2 */ | |
if (i8237_rD) { /* high byte */ | |
i8237_rD = 0; | |
i8237_r4 |= (data << 8); | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r4(H) set to %04X\n", i8237_r4); | |
} else { /* low byte */ | |
i8237_rD++; | |
i8237_r4 = data & 0xFF; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r4(L) set to %04X\n", i8237_r4); | |
} | |
return 0; | |
} | |
} | |
uint8 isbc208_r5(t_bool io, uint8 data) | |
{ | |
if (io == 0) { /* read current word count CH 2 */ | |
if (i8237_rD) { /* high byte */ | |
i8237_rD = 0; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r5(H) read as %04X\n", i8237_r5); | |
return (i8237_r5 >> 8); | |
} else { /* low byte */ | |
i8237_rD++; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r5(L) read as %04X\n", i8237_r5); | |
return (i8237_r5 & 0xFF); | |
} | |
} else { /* write base & current address CH 2 */ | |
if (i8237_rD) { /* high byte */ | |
i8237_rD = 0; | |
i8237_r5 |= (data << 8); | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r5(H) set to %04X\n", i8237_r5); | |
} else { /* low byte */ | |
i8237_rD++; | |
i8237_r5 = data & 0xFF; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r5(L) set to %04X\n", i8237_r5); | |
} | |
return 0; | |
} | |
} | |
uint8 isbc208_r6(t_bool io, uint8 data) | |
{ | |
if (io == 0) { /* read current address CH 3 */ | |
if (i8237_rD) { /* high byte */ | |
i8237_rD = 0; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r6(H) read as %04X\n", i8237_r6); | |
return (i8237_r6 >> 8); | |
} else { /* low byte */ | |
i8237_rD++; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r6(L) read as %04X\n", i8237_r6); | |
return (i8237_r6 & 0xFF); | |
} | |
} else { /* write base & current address CH 3 */ | |
if (i8237_rD) { /* high byte */ | |
i8237_rD = 0; | |
i8237_r6 |= (data << 8); | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r6(H) set to %04X\n", i8237_r6); | |
} else { /* low byte */ | |
i8237_rD++; | |
i8237_r6 = data & 0xFF; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r6(L) set to %04X\n", i8237_r6); | |
} | |
return 0; | |
} | |
} | |
uint8 isbc208_r7(t_bool io, uint8 data) | |
{ | |
if (io == 0) { /* read current word count CH 3 */ | |
if (i8237_rD) { /* high byte */ | |
i8237_rD = 0; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r7(H) read as %04X\n", i8237_r7); | |
return (i8237_r7 >> 8); | |
} else { /* low byte */ | |
i8237_rD++; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r7(L) read as %04X\n", i8237_r7); | |
return (i8237_r7 & 0xFF); | |
} | |
} else { /* write base & current address CH 3 */ | |
if (i8237_rD) { /* high byte */ | |
i8237_rD = 0; | |
i8237_r7 |= (data << 8); | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r7(H) set to %04X\n", i8237_r7); | |
} else { /* low byte */ | |
i8237_rD++; | |
i8237_r7 = data & 0xFF; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r7(L) set to %04X\n", i8237_r7); | |
} | |
return 0; | |
} | |
} | |
uint8 isbc208_r8(t_bool io, uint8 data) | |
{ | |
if (io == 0) { /* read status register */ | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r8 (status) read as %02X\n", i8237_r8); | |
return (i8237_r8); | |
} else { /* write command register */ | |
i8237_r9 = data & 0xFF; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_r9 (command) set to %02X\n", i8237_r9); | |
return 0; | |
} | |
} | |
uint8 isbc208_r9(t_bool io, uint8 data) | |
{ | |
if (io == 0) { | |
sim_debug (DEBUG_reg, &isbc208_dev, "Illegal read of isbc208_r9\n"); | |
return 0; | |
} else { /* write request register */ | |
i8237_rC = data & 0xFF; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_rC (request) set to %02X\n", i8237_rC); | |
return 0; | |
} | |
} | |
uint8 isbc208_rA(t_bool io, uint8 data) | |
{ | |
if (io == 0) { | |
sim_debug (DEBUG_reg, &isbc208_dev, "Illegal read of isbc208_rA\n"); | |
return 0; | |
} else { /* write single mask register */ | |
switch(data & 0x03) { | |
case 0: | |
if (data & 0x04) | |
i8237_rB |= 1; | |
else | |
i8237_rB &= ~1; | |
break; | |
case 1: | |
if (data & 0x04) | |
i8237_rB |= 2; | |
else | |
i8237_rB &= ~2; | |
break; | |
case 2: | |
if (data & 0x04) | |
i8237_rB |= 4; | |
else | |
i8237_rB &= ~4; | |
break; | |
case 3: | |
if (data & 0x04) | |
i8237_rB |= 8; | |
else | |
i8237_rB &= ~8; | |
break; | |
} | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_rB (mask) set to %02X\n", i8237_rB); | |
return 0; | |
} | |
} | |
uint8 isbc208_rB(t_bool io, uint8 data) | |
{ | |
if (io == 0) { | |
sim_debug (DEBUG_reg, &isbc208_dev, "Illegal read of isbc208_rB\n"); | |
return 0; | |
} else { /* write mode register */ | |
i8237_rA = data & 0xFF; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_rA (mode) set to %02X\n", i8237_rA); | |
return 0; | |
} | |
} | |
uint8 isbc208_rC(t_bool io, uint8 data) | |
{ | |
if (io == 0) { | |
sim_debug (DEBUG_reg, &isbc208_dev, "Illegal read of isbc208_rC\n"); | |
return 0; | |
} else { /* clear byte pointer FF */ | |
i8237_rD = 0; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_rD (FF) cleared\n"); | |
return 0; | |
} | |
} | |
uint8 isbc208_rD(t_bool io, uint8 data) | |
{ | |
if (io == 0) { /* read temporary register */ | |
sim_debug (DEBUG_reg, &isbc208_dev, "Illegal read of isbc208_rD\n"); | |
return 0; | |
} else { /* master clear */ | |
isbc208_reset1(); | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237 master clear\n"); | |
return 0; | |
} | |
} | |
uint8 isbc208_rE(t_bool io, uint8 data) | |
{ | |
if (io == 0) { | |
sim_debug (DEBUG_reg, &isbc208_dev, "Illegal read of isbc208_rE\n"); | |
return 0; | |
} else { /* clear mask register */ | |
i8237_rB = 0; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_rB (mask) cleared\n"); | |
return 0; | |
} | |
} | |
uint8 isbc208_rF(t_bool io, uint8 data) | |
{ | |
if (io == 0) { | |
sim_debug (DEBUG_reg, &isbc208_dev, "Illegal read of isbc208_rF\n"); | |
return 0; | |
} else { /* write all mask register bits */ | |
i8237_rB = data & 0x0F; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8237_rB (mask) set to %02X\n", i8237_rB); | |
return 0; | |
} | |
} | |
uint8 isbc208_r10(t_bool io, uint8 data) | |
{ | |
if (io == 0) { /* read FDC status register */ | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8272_msr read as %02X\n", i8272_msr); | |
return i8272_msr; | |
} else { | |
sim_debug (DEBUG_reg, &isbc208_dev, "Illegal write to isbc208_r10\n"); | |
return 0; | |
} | |
} | |
// read/write FDC data register | |
uint8 isbc208_r11(t_bool io, uint8 data) | |
{ | |
if (io == 0) { /* read FDC data register */ | |
wsp = 0; /* clear write stack index */ | |
switch (rsp) { /* read from next stack register */ | |
case 0: | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8272_r1 read as %02X\n", i8272_r1); | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8272_r3 read as %02X\n", i8272_r3); | |
rsp++; /* step read stack index */ | |
clr_irq(SBC208_INT); /* clear interrupt */ | |
if (pcmd == SENDRV) { | |
i8272_msr = RQM; /* result phase SENDRV done */ | |
return i8272_r1; // SENDRV return ST1 | |
} | |
return i8272_r0; /* ST0 */ | |
case 1: | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8272_r2 read as %02X\n", i8272_r2); | |
rsp++; /* step read stack index */ | |
if (pcmd == SENINT) { | |
i8272_msr = RQM; /* result phase SENINT done */ | |
return cyl; // SENINT return current cylinder | |
} | |
return i8272_r1; /* ST1 */ | |
case 2: | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8272_r3 read as %02X\n", i8272_r3); | |
rsp++; /* step read stack index */ | |
return i8272_r2; /* ST2 */ | |
case 3: | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8272_w2 read as %02X\n", i8272_w2); | |
rsp++; /* step read stack index */ | |
return i8272_w2; /* C - cylinder */ | |
case 4: | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8272_w3 read as %02X\n", i8272_w3); | |
rsp++; /* step read stack index */ | |
return i8272_w3; /* H - head */ | |
case 5: | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8272_w4 read as %02X\n", i8272_w4); | |
rsp++; /* step read stack index */ | |
return i8272_w4; /* R - sector */ | |
case 6: | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8272_w5 read as %02X\n", i8272_w5); | |
i8272_msr = RQM; /* result phase ALL OTHERS done */ | |
return i8272_w5; /* N - sector size*/ | |
} | |
} else { /* write FDC data register */ | |
rsp = 0; /* clear read stack index */ | |
switch (wsp) { /* write to next stack register */ | |
case 0: | |
i8272_w0 = data; /* rws = MT + MFM + SK + cmd */ | |
cmd = data & 0x1F; /* save the current command */ | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8272_w0 set to %02X\n", data); | |
if (cmd == SENINT) { | |
i8272_msr = CB; /* command phase SENINT done */ | |
return 0; | |
} | |
wsp++; /* step write stack index */ | |
break; | |
case 1: | |
i8272_w1 = data; /* rws = hed + drv */ | |
if (cmd != SPEC) | |
drv = data & 0x03; | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8272_w1 set to %02X\n", data); | |
if (cmd == HOME || cmd == SENDRV || cmd == READID) { | |
i8272_msr = CB + hed + drv; /* command phase HOME, READID and SENDRV done */ | |
return 0; | |
} | |
wsp++; /* step write stack index */ | |
break; | |
case 2: | |
i8272_w2 = data; /* rws = C */ | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8272_w2 set to %02X\n", data); | |
if (cmd == SPEC || cmd == SEEK) { | |
i8272_msr = CB + hed + drv; /* command phase SPECIFY and SEEK done */ | |
return 0; | |
} | |
wsp++; /* step write stack index */ | |
break; | |
case 3: | |
i8272_w3 = data; /* rw = H */ | |
hed = data; | |
wsp++; /* step write stack index */ | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8272_w3 set to %02X\n", data); | |
break; | |
case 4: | |
i8272_w4 = data; /* rw = R */ | |
sec = data; | |
wsp++; /* step write stack index */ | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8272_w4 set to %02X\n", data); | |
break; | |
case 5: | |
i8272_w5 = data; /* rw = N */ | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8272_w5 set to %02X\n", data); | |
if (cmd == FMTTRK) { | |
i8272_msr = CB + hed + drv; /* command phase FMTTRK done */ | |
return 0; | |
} | |
wsp++; /* step write stack index */ | |
break; | |
case 6: | |
i8272_w6 = data; /* rw = last sector number */ | |
wsp++; /* step write stack index */ | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8272_w6 set to %02X\n", data); | |
break; | |
case 7: | |
i8272_w7 = data; /* rw = gap length */ | |
wsp++; /* step write stack index */ | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8272_w7 set to %02X\n", data); | |
break; | |
case 8: | |
i8272_w8 = data; /* rw = bytes to transfer */ | |
sim_debug (DEBUG_reg, &isbc208_dev, "i8272_w8 set to %02X\n", data); | |
if (cmd == READ || cmd == WRITE) | |
i8272_msr = CB + hed + drv; /* command phase all others done */ | |
break; | |
} | |
} | |
return 0; | |
} | |
uint8 isbc208_r12(t_bool io, uint8 data) | |
{ | |
if (io == 0) { /* read interrupt status */ | |
sim_debug (DEBUG_reg, &isbc208_dev, "isbc208_r12 read as %02X\n", isbc208_i); | |
return (isbc208_i); | |
} else { /* write controller auxillary port */ | |
isbc208_a = data & 0xFF; | |
sim_debug (DEBUG_reg, &isbc208_dev, "isbc208_r12 set to %02X\n", isbc208_a); | |
return 0; | |
} | |
} | |
uint8 isbc208_r13(t_bool io, uint8 data) | |
{ | |
if (io == 0) { | |
sim_debug (DEBUG_reg, &isbc208_dev, "Illegal read of isbc208_r13\n"); | |
return 0; | |
} else { /* reset controller */ | |
isbc208_reset1(); | |
sim_debug (DEBUG_reg, &isbc208_dev, "isbc208_r13 controller reset\n"); | |
return 0; | |
} | |
} | |
uint8 isbc208_r14(t_bool io, uint8 data) | |
{ | |
if (io == 0) { | |
sim_debug (DEBUG_reg, &isbc208_dev, "Illegal read of isbc208_r14\n"); | |
return 0; | |
} else { /* Low-Byte Segment Address Register */ | |
isbc208_sr = data & 0xFF; | |
sim_debug (DEBUG_reg, &isbc208_dev, "isbc208_sr(L) set to %02X\n", data & 0xFF); | |
return 0; | |
} | |
} | |
uint8 isbc208_r15(t_bool io, uint8 data) | |
{ | |
if (io == 0) { | |
sim_debug (DEBUG_reg, &isbc208_dev, "Illegal read of isbc208_r15\n"); | |
return 0; | |
} else { /* High-Byte Segment Address Register */ | |
isbc208_sr |= data << 8; | |
sim_debug (DEBUG_reg, &isbc208_dev, "isbc208_sr(H) set to %02X\n", data); | |
return 0; | |
} | |
} | |
/* end of isbc208.c */ |