| /* 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. |
| 16 Dec 12 - Modified to use isbc_80_10.cfg file to set base and size. |
| 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 |
| |
| /* internal function prototypes */ |
| |
| t_stat isbc208_svc (UNIT *uptr); |
| t_stat isbc208_reset (DEVICE *dptr); |
| void isbc208_reset1 (void); |
| t_stat isbc208_attach (UNIT *uptr, char *cptr); |
| t_stat isbc208_set_mode (UNIT *uptr, int32 val, char *cptr, void *desc); |
| int32 isbc208_r0(int32 io, int32 data); |
| int32 isbc208_r1(int32 io, int32 data); |
| int32 isbc208_r2(int32 io, int32 data); |
| int32 isbc208_r3(int32 io, int32 data); |
| int32 isbc208_r4(int32 io, int32 data); |
| int32 isbc208_r5(int32 io, int32 data); |
| int32 isbc208_r6(int32 io, int32 data); |
| int32 isbc208_r7(int32 io, int32 data); |
| int32 isbc208_r8(int32 io, int32 data); |
| int32 isbc208_r9(int32 io, int32 data); |
| int32 isbc208_rA(int32 io, int32 data); |
| int32 isbc208_rB(int32 io, int32 data); |
| int32 isbc208_rC(int32 io, int32 data); |
| int32 isbc208_rD(int32 io, int32 data); |
| int32 isbc208_rE(int32 io, int32 data); |
| int32 isbc208_rF(int32 io, int32 data); |
| int32 isbc208_r10(int32 io, int32 data); |
| int32 isbc208_r11(int32 io, int32 data); |
| int32 isbc208_r12(int32 io, int32 data); |
| int32 isbc208_r13(int32 io, int32 data); |
| int32 isbc208_r14(int32 io, int32 data); |
| int32 isbc208_r15(int32 io, int32 data); |
| |
| /* external function prototypes */ |
| |
| extern void set_irq(int32 int_num); |
| extern void clr_irq(int32 int_num); |
| extern int32 reg_dev(int32 (*routine)(), int32 port); |
| extern void multibus_put_mbyte(int32 addr, int32 val); |
| extern int32 multibus_get_mbyte(int32 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 |
| |
| /* 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, //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, "isbc208_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, |
| "isbc208_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, |
| "isbc208_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_flow, &isbc208_dev, "\nFDC read of d=%d h=%d c=%d s=%d", |
| 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, "isbc208_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_flow, &isbc208_dev, |
| "isbc208_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, |
| "isbc208_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, |
| "isbc208_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]); |
| 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, "isbc208_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("isbc208_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_flow, &isbc208_dev, |
| "isbc208_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, "isbc208_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, "isbc208_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, "isbc208_svc: FDC sense drive of disk=%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, "isbc208_svc: FDC home: disk=%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, "isbc208_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, |
| "isbc208_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, "isbc208_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, "isbc208_svc: FDC seek: disk=%d cyl=%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, "isbc208_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, "isbc208_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, |
| "isbc208_svc: Exit: RSLT0 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; |
| } |
| |
| // read/write FDC data register |
| int32 isbc208_r11(int32 io, int32 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; |
| } |
| |
| /* Reset routine */ |
| |
| t_stat isbc208_reset (DEVICE *dptr) |
| { |
| reg_dev(isbc208_r0, SBC208_BASE + 0); |
| reg_dev(isbc208_r1, SBC208_BASE + 1); |
| reg_dev(isbc208_r2, SBC208_BASE + 2); |
| reg_dev(isbc208_r3, SBC208_BASE + 3); |
| reg_dev(isbc208_r4, SBC208_BASE + 4); |
| reg_dev(isbc208_r5, SBC208_BASE + 5); |
| reg_dev(isbc208_r6, SBC208_BASE + 6); |
| reg_dev(isbc208_r7, SBC208_BASE + 7); |
| reg_dev(isbc208_r8, SBC208_BASE + 8); |
| reg_dev(isbc208_r9, SBC208_BASE + 9); |
| reg_dev(isbc208_rA, SBC208_BASE + 10); |
| reg_dev(isbc208_rB, SBC208_BASE + 11); |
| reg_dev(isbc208_rC, SBC208_BASE + 12); |
| reg_dev(isbc208_rD, SBC208_BASE + 13); |
| reg_dev(isbc208_rE, SBC208_BASE + 14); |
| reg_dev(isbc208_rF, SBC208_BASE + 15); |
| reg_dev(isbc208_r10, SBC208_BASE + 16); |
| reg_dev(isbc208_r11, SBC208_BASE + 17); |
| reg_dev(isbc208_r12, SBC208_BASE + 18); |
| reg_dev(isbc208_r13, SBC208_BASE + 19); |
| reg_dev(isbc208_r14, SBC208_BASE + 20); |
| reg_dev(isbc208_r15, SBC208_BASE + 21); |
| if ((isbc208_dev.flags & DEV_DIS) == 0) |
| isbc208_reset1(); |
| 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 */ |
| 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, 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 (isbc208_buf[uptr->u6] == NULL) { /* no buffer allocated */ |
| isbc208_buf[uptr->u6] = 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 */ |
| |
| t_stat isbc208_set_mode (UNIT *uptr, int32 val, 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. |
| */ |
| |
| int32 isbc208_r0(int32 io, int32 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; |
| } |
| } |
| |
| int32 isbc208_r1(int32 io, int32 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; |
| } |
| } |
| |
| int32 isbc208_r2(int32 io, int32 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; |
| } |
| } |
| |
| int32 isbc208_r3(int32 io, int32 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; |
| } |
| } |
| |
| int32 isbc208_r4(int32 io, int32 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; |
| } |
| } |
| |
| int32 isbc208_r5(int32 io, int32 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; |
| } |
| } |
| |
| int32 isbc208_r6(int32 io, int32 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; |
| } |
| } |
| |
| int32 isbc208_r7(int32 io, int32 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; |
| } |
| } |
| |
| int32 isbc208_r8(int32 io, int32 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; |
| } |
| } |
| |
| int32 isbc208_r9(int32 io, int32 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; |
| } |
| } |
| |
| int32 isbc208_rA(int32 io, int32 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; |
| } |
| } |
| |
| int32 isbc208_rB(int32 io, int32 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; |
| } |
| } |
| |
| int32 isbc208_rC(int32 io, int32 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; |
| } |
| } |
| |
| int32 isbc208_rD(int32 io, int32 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; |
| } |
| } |
| |
| int32 isbc208_rE(int32 io, int32 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; |
| } |
| } |
| |
| int32 isbc208_rF(int32 io, int32 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; |
| } |
| } |
| |
| int32 isbc208_r10(int32 io, int32 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; |
| } |
| } |
| |
| int32 isbc208_r12(int32 io, int32 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; |
| } |
| } |
| |
| int32 isbc208_r13(int32 io, int32 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; |
| } |
| } |
| |
| int32 isbc208_r14(int32 io, int32 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; |
| } |
| } |
| |
| int32 isbc208_r15(int32 io, int32 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 */ |