/* iPATA.c: Intel i8255 PIO adapter for PATA HD | |
Copyright (c) 2015, 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. | |
NOTES: | |
These functions support a simulated i8255 interface device on an iSBC. | |
The device has threee physical 8-bit I/O ports which could be connected | |
to any parallel I/O device. This is an extension of the i8255.c file to support | |
an emulated PATA IDE Hard Disk Drive. | |
All I/O is via programmed I/O. The i8255 has a control port (PIOS) | |
and three data ports (PIOA, PIOB, and PIOC). | |
The simulated device supports a select from I/O space and two address lines. | |
The data ports are at the lower addresses and the control port is at | |
the highest. | |
A write to the control port can configure the device: | |
Control Word | |
+---+---+---+---+---+---+---+---+ | |
| D7 D6 D5 D4 D3 D2 D1 D0| | |
+---+---+---+---+---+---+---+---+ | |
Group B | |
D0 Port C (lower) 1-Input, 0-Output | |
D1 Port B 1-Input, 0-Output | |
D2 Mode Selection 0-Mode 0, 1-Mode 1 | |
Group A | |
D3 Port C (upper) 1-Input, 0-Output | |
D4 Port A 1-Input, 0-Output | |
D5-6 Mode Selection 00-Mode 0, 01-Mode 1, 1X-Mode 2 | |
D7 Mode Set Flag 1=Active, 0=Bit Set | |
Mode 0 - Basic Input/Output | |
Mode 1 - Strobed Input/Output | |
Mode 2 - Bidirectional Bus | |
Bit Set - D7=0, D3:1 select port C bit, D0 1=set, 0=reset | |
A read to the data ports gets the current port value, a write | |
to the data ports writes the character to the device. | |
The Second 8255 on the iSBC 80/10 is used to connect to the IDE PATA | |
Hard Disk Drive. Pins are defined as shown below: | |
PA[0..7] High data byte | |
PB[0..7] Low data byte | |
PC[0..2] Register select | |
PC[3..4] CSFX select | |
PC[5] Read register | |
PC[6] Write register | |
*/ | |
#include "system_defs.h" | |
extern int32 reg_dev(int32 (*routine)(), int32 port); | |
/* function prototypes */ | |
t_stat pata_reset (DEVICE *dptr, int32 base); | |
/* i8255 Standard I/O Data Structures */ | |
UNIT pata_unit[] = { | |
{ UDATA (0, 0, 0) } | |
}; | |
REG pata_reg[] = { | |
{ HRDATA (CONTROL0, pata_unit[0].u3, 8) }, | |
{ HRDATA (PORTA0, pata_unit[0].u4, 8) }, | |
{ HRDATA (PORTB0, pata_unit[0].u5, 8) }, | |
{ HRDATA (PORTC0, pata_unit[0].u6, 8) }, | |
{ NULL } | |
}; | |
DEVICE pata_dev = { | |
"PATA", //name | |
pata_unit, //units | |
pata_reg, //registers | |
NULL, //modifiers | |
1, //numunits | |
16, //aradix | |
32, //awidth | |
1, //aincr | |
16, //dradix | |
8, //dwidth | |
NULL, //examine | |
NULL, //deposit | |
// &pata_reset, //reset | |
NULL, //reset | |
NULL, //boot | |
NULL, //attach | |
NULL, //detach | |
NULL, //ctxt | |
0, //flags | |
0, //dctrl | |
NULL, //debflags | |
NULL, //msize | |
NULL //lname | |
}; | |
/* I/O instruction handlers, called from the CPU module when an | |
IN or OUT instruction is issued. | |
*/ | |
int32 patas(int32 io, int32 data) | |
{ | |
int32 bit; | |
if (io == 0) { /* read status port */ | |
return pata_unit[0].u3; | |
} else { /* write status port */ | |
if (data & 0x80) { /* mode instruction */ | |
pata_unit[0].u3 = data; | |
sim_printf("PATA: 8255 Mode Instruction=%02X\n", data); | |
if (data & 0x64) | |
sim_printf(" Mode 1 and 2 not yet implemented\n"); | |
} else { /* bit set */ | |
bit = (data & 0x0E) >> 1; /* get bit number */ | |
if (data & 0x01) { /* set bit */ | |
pata_unit[0].u6 |= (0x01 << bit); | |
} else { /* reset bit */ | |
pata_unit[0].u6 &= ~(0x01 << bit); | |
} | |
} | |
} | |
return 0; | |
} | |
int32 pataa(int32 io, int32 data) | |
{ | |
if (io == 0) { /* read data port */ | |
sim_printf("PATA: 8255 Read Port A = %02X\n", pata_unit[0].u4); | |
return (pata_unit[0].u4); | |
} else { /* write data port */ | |
pata_unit[0].u4 = data; | |
sim_printf("PATA: 8255 Write Port A = %02X\n", data); | |
} | |
return 0; | |
} | |
int32 patab(int32 io, int32 data) | |
{ | |
if (io == 0) { /* read data port */ | |
sim_printf("PATA: 8255 Read Port B = %02X\n", pata_unit[0].u5); | |
return (pata_unit[0].u5); | |
} else { /* write data port */ | |
pata_unit[0].u5 = data; | |
sim_printf("PATA: 8255 Write Port B = %02X\n", data); | |
} | |
return 0; | |
} | |
int32 patac(int32 io, int32 data) | |
{ | |
if (io == 0) { /* read data port */ | |
sim_printf("PATA: 8255 Read Port C = %02X\n", pata_unit[0].u6); | |
return (pata_unit[0].u6); | |
} else { /* write data port */ | |
pata_unit[0].u6 = data; | |
sim_printf("PATA: 8255 Write Port C = %02X\n", data); | |
} | |
return 0; | |
} | |
/* Reset routine */ | |
t_stat pata_reset (DEVICE *dptr, int32 base) | |
{ | |
pata_unit[0].u3 = 0x9B; /* control */ | |
pata_unit[0].u4 = 0xFF; /* Port A */ | |
pata_unit[0].u5 = 0xFF; /* Port B */ | |
pata_unit[0].u6 = 0xFF; /* Port C */ | |
reg_dev(pataa, base); | |
reg_dev(patab, base + 1); | |
reg_dev(patac, base + 2); | |
reg_dev(patas, base + 3); | |
sim_printf(" PATA: Reset\n"); | |
return SCPE_OK; | |
} | |