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Diffstat (limited to 'src/mess/drivers/imds2.c')
-rw-r--r--src/mess/drivers/imds2.c149
1 files changed, 129 insertions, 20 deletions
diff --git a/src/mess/drivers/imds2.c b/src/mess/drivers/imds2.c
index 89de9892f3b..0eb65373a96 100644
--- a/src/mess/drivers/imds2.c
+++ b/src/mess/drivers/imds2.c
@@ -35,7 +35,7 @@
//
// This board acts as a controller for all I/O of the system.
// It is structured as if it were 2 boards in one:
-// One part (around 8080) controls Keyboard, CRT & floppy, the other part (around PIO 8741) controls all parallel I/Os
+// One part (around 8080) controls Keyboard, CRT & floppy, the other part (around PIO 8041A) controls all parallel I/Os
// (Line printer, Paper tape puncher, Paper tape reader, I/O to PROM programmer).
// Both parts are interfaced to IPC through a bidirectional 8-bit bus.
// IOC is composed of these parts:
@@ -51,7 +51,7 @@
// A20 8275 CRT controller
// A19 2708 Character generator ROM
// LS1 3.3 kHz beeper
-//*A72 8741-4 CPU @ 6 MHz (PIO: parallel I/O)
+// A72 8041A CPU @ 6 MHz (PIO: parallel I/O)
//
// **********
// Keyboard controller
@@ -62,10 +62,13 @@
//
// ICs that are not emulated yet are marked with "*"
//
+// NOTE:
+// Firmware running on PIO is NOT original because a dump is not available at the moment.
+// Emulator runs a version of PIO firmware that was specifically developped by me to implement
+// line printer output.
+//
// TODO:
-// - Improve keyboard mapping
-// - Emulate PIO. No known dumps of its ROM are available, though.
-// - Emulate line printer output on PIO
+// - Find a dump of the original PIO firmware
// - Emulate serial channels on IPC
// - Emulate PIT on IPC
// - Adjust speed of processors. Wait states are not accounted for yet.
@@ -87,8 +90,6 @@
// should be mounted and the system reset. After a few seconds the ISIS-II
// prompt should appear. A command that could be tried is "DIR" that lists
// the content of floppy disk.
-// Please note that the message "FAILURE -- PIO NOT RESPONDING" is normal
-// as the support for PIO isn't implemented yet
#include "includes/imds2.h"
@@ -101,6 +102,9 @@
// FDC oscillator of IOC board: 8 MHz
#define IOC_XTAL_Y1 XTAL_8MHz
+// PIO oscillator: 6 MHz
+#define IOC_XTAL_Y3 XTAL_6MHz
+
// Frequency of beeper
#define IOC_BEEP_FREQ 3300
@@ -112,12 +116,13 @@ static ADDRESS_MAP_START(ipc_io_map , AS_IO , 8 , imds2_state)
ADDRESS_MAP_UNMAP_LOW
AM_RANGE(0xc0 , 0xc0) AM_READWRITE(imds2_ipc_dbbout_r , imds2_ipc_dbbin_data_w)
AM_RANGE(0xc1 , 0xc1) AM_READWRITE(imds2_ipc_status_r , imds2_ipc_dbbin_cmd_w)
+ AM_RANGE(0xf8 , 0xf9) AM_DEVREADWRITE("iocpio" , i8041_device , upi41_master_r , upi41_master_w)
AM_RANGE(0xfa , 0xfb) AM_READWRITE(imds2_ipclocpic_r , imds2_ipclocpic_w)
AM_RANGE(0xfc , 0xfd) AM_READWRITE(imds2_ipcsyspic_r , imds2_ipcsyspic_w)
AM_RANGE(0xff , 0xff) AM_WRITE(imds2_ipc_control_w)
ADDRESS_MAP_END
- static ADDRESS_MAP_START(ioc_mem_map , AS_PROGRAM , 8 , imds2_state)
+static ADDRESS_MAP_START(ioc_mem_map , AS_PROGRAM , 8 , imds2_state)
ADDRESS_MAP_UNMAP_HIGH
AM_RANGE(0x0000 , 0x1fff) AM_ROM
AM_RANGE(0x4000 , 0x5fff) AM_RAM
@@ -143,6 +148,11 @@ static ADDRESS_MAP_START(ioc_io_map , AS_IO , 8 , imds2_state)
AM_RANGE(0xf0 , 0xf8) AM_DEVREADWRITE("iocdma" , i8257_device , read , write)
ADDRESS_MAP_END
+static ADDRESS_MAP_START(pio_io_map , AS_IO , 8 , imds2_state)
+ AM_RANGE(MCS48_PORT_P1 , MCS48_PORT_P1) AM_READWRITE(imds2_pio_port_p1_r , imds2_pio_port_p1_w)
+ AM_RANGE(MCS48_PORT_P2 , MCS48_PORT_P2) AM_READWRITE(imds2_pio_port_p2_r , imds2_pio_port_p2_w)
+ADDRESS_MAP_END
+
static ADDRESS_MAP_START(kb_io_map , AS_IO , 8 , imds2_state)
AM_RANGE(MCS48_PORT_P1 , MCS48_PORT_P1) AM_WRITE(imds2_kb_port_p1_w)
AM_RANGE(MCS48_PORT_P2 , MCS48_PORT_P2) AM_READ(imds2_kb_port_p2_r)
@@ -161,10 +171,12 @@ imds2_state::imds2_state(const machine_config &mconfig, device_type type, const
m_iocbeep(*this , "iocbeep"),
m_ioctimer(*this , "ioctimer"),
m_iocfdc(*this , "iocfdc"),
+ m_iocpio(*this , "iocpio"),
m_kbcpu(*this , "kbcpu"),
m_palette(*this , "palette"),
m_gfxdecode(*this, "gfxdecode"),
m_floppy0(*this , FLOPPY_0),
+ m_centronics(*this , "centronics"),
m_io_key0(*this , "KEY0"),
m_io_key1(*this , "KEY1"),
m_io_key2(*this , "KEY2"),
@@ -173,7 +185,8 @@ imds2_state::imds2_state(const machine_config &mconfig, device_type type, const
m_io_key5(*this , "KEY5"),
m_io_key6(*this , "KEY6"),
m_io_key7(*this , "KEY7"),
- m_ioc_options(*this , "IOC_OPTS")
+ m_ioc_options(*this , "IOC_OPTS"),
+ m_device_status_byte(0xff)
{
}
@@ -370,7 +383,7 @@ WRITE8_MEMBER(imds2_state::imds2_ioc_reset_f1_w)
READ8_MEMBER(imds2_state::imds2_ioc_status_r)
{
- return (~m_ipc_ioc_status & 0x0f) | 0xf0;
+ return ~m_ipc_ioc_status;
}
READ8_MEMBER(imds2_state::imds2_ioc_dbbin_r)
@@ -428,6 +441,64 @@ WRITE8_MEMBER(imds2_state::imds2_ioc_mem_w)
return prog_space.write_byte(offset , data);
}
+READ8_MEMBER(imds2_state::imds2_pio_port_p1_r)
+{
+ // If STATUS ENABLE/ == 0 return inverted device status byte, else return 0xff
+ // STATUS ENABLE/ == 0 when P23-P20 == 12 & P24 == 0 & P25 = 1 & P26 = 1
+ if ((m_pio_port2 & 0x7f) == 0x6c) {
+ return ~m_device_status_byte;
+ } else {
+ return 0xff;
+}
+}
+
+WRITE8_MEMBER(imds2_state::imds2_pio_port_p1_w)
+{
+ m_pio_port1 = data;
+ imds2_update_printer();
+}
+
+READ8_MEMBER(imds2_state::imds2_pio_port_p2_r)
+{
+ return m_pio_port2;
+}
+
+WRITE8_MEMBER(imds2_state::imds2_pio_port_p2_w)
+{
+ m_pio_port2 = data;
+ imds2_update_printer();
+ // Send INTR to IPC
+ m_ipclocpic->ir5_w(BIT(data , 7));
+}
+
+WRITE_LINE_MEMBER(imds2_state::imds2_pio_lpt_ack_w)
+{
+ if (state) {
+ m_device_status_byte |= 0x20;
+ } else {
+ m_device_status_byte &= ~0x20;
+ }
+}
+
+WRITE_LINE_MEMBER(imds2_state::imds2_pio_lpt_busy_w)
+{
+ // Busy is active high in centronics_device whereas it's active low in MDS
+ if (!state) {
+ m_device_status_byte |= 0x10;
+ } else {
+ m_device_status_byte &= ~0x10;
+ }
+}
+
+WRITE_LINE_MEMBER(imds2_state::imds2_pio_lpt_select_w)
+{
+ if (state) {
+ m_device_status_byte |= 0x40;
+ } else {
+ m_device_status_byte &= ~0x40;
+ }
+}
+
I8275_DRAW_CHARACTER_MEMBER(imds2_state::crtc_display_pixels)
{
unsigned i;
@@ -538,18 +609,40 @@ void imds2_state::imds2_update_beeper(void)
m_iocbeep->set_state(m_beeper_timer == 0 && BIT(m_miscout , 0) == 0);
}
+void imds2_state::imds2_update_printer(void)
+{
+ // Data to printer is ~P1 when STATUS ENABLE/==1, else 0xff (assuming pull-ups on printer)
+ UINT8 printer_data;
+ if ((m_pio_port2 & 0x7f) == 0x6c) {
+ printer_data = 0xff;
+ } else {
+ printer_data = ~m_pio_port1;
+ }
+ m_centronics->write_data0(BIT(printer_data , 0));
+ m_centronics->write_data1(BIT(printer_data , 1));
+ m_centronics->write_data2(BIT(printer_data , 2));
+ m_centronics->write_data3(BIT(printer_data , 3));
+ m_centronics->write_data4(BIT(printer_data , 4));
+ m_centronics->write_data5(BIT(printer_data , 5));
+ m_centronics->write_data6(BIT(printer_data , 6));
+ m_centronics->write_data7(BIT(printer_data , 7));
+
+ // LPT DATA STROBE/ == 0 when P23-P20 == 9 & P24 == 0
+ m_centronics->write_strobe((m_pio_port2 & 0x1f) != 0x09);
+}
+
static INPUT_PORTS_START(imds2)
// See [1], pg 56 for key matrix layout
// See [1], pg 57 for keyboard layout
PORT_START("KEY0")
PORT_BIT(0x01 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_TAB) PORT_CHAR('\t') // OK
- PORT_BIT(0x02 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_OPENBRACE) PORT_CHAR('@') PORT_CHAR('`')
+ PORT_BIT(0x02 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_COLON) PORT_CHAR('@') PORT_CHAR('`') // OK
PORT_BIT(0x04 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_COMMA) PORT_CHAR(',') PORT_CHAR('<') // OK
PORT_BIT(0x08 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_ENTER) PORT_CHAR(13) // OK
- PORT_BIT(0x10 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_SPACE) PORT_CHAR(' ')
- PORT_BIT(0x20 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_QUOTE) PORT_CHAR(':') PORT_CHAR('*') // '
- PORT_BIT(0x40 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_STOP) PORT_CHAR('.') PORT_CHAR('>') // .
- PORT_BIT(0x80 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_SLASH) PORT_CHAR('/') PORT_CHAR('?')
+ PORT_BIT(0x10 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_SPACE) PORT_CHAR(' ') // OK
+ PORT_BIT(0x20 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_BACKSLASH) PORT_CHAR(':') PORT_CHAR('*') // OK
+ PORT_BIT(0x40 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_STOP) PORT_CHAR('.') PORT_CHAR('>') // OK
+ PORT_BIT(0x80 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_SLASH) PORT_CHAR('/') PORT_CHAR('?') // OK
PORT_START("KEY1")
PORT_BIT(0x01 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_Z) PORT_CHAR('z') PORT_CHAR('Z') // OK
@@ -563,13 +656,13 @@ static INPUT_PORTS_START(imds2)
PORT_START("KEY2")
PORT_BIT(0x01 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_0) PORT_CHAR('0') PORT_CHAR('~') // OK
- PORT_BIT(0x02 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_OPENBRACE) PORT_CHAR('[') PORT_CHAR('{')
+ PORT_BIT(0x02 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_OPENBRACE) PORT_CHAR('[') PORT_CHAR('{') // OK
PORT_BIT(0x04 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_O) PORT_CHAR('o') PORT_CHAR('O') // OK
PORT_BIT(0x08 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_L) PORT_CHAR('l') PORT_CHAR('L') // OK
PORT_BIT(0x10 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_9) PORT_CHAR('9') PORT_CHAR(')') // OK
PORT_BIT(0x20 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_MINUS) PORT_CHAR('-') PORT_CHAR('=') // OK
PORT_BIT(0x40 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_P) PORT_CHAR('p') PORT_CHAR('P') // OK
- PORT_BIT(0x80 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_COLON) PORT_CHAR(';') PORT_CHAR('+')
+ PORT_BIT(0x80 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_QUOTE) PORT_CHAR(';') PORT_CHAR('+') // OK
PORT_START("KEY3")
PORT_BIT(0x01 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_S) PORT_CHAR('s') PORT_CHAR('S') // OK
@@ -604,17 +697,17 @@ static INPUT_PORTS_START(imds2)
PORT_START("KEY6")
PORT_BIT(0x01 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_BACKSPACE) PORT_CHAR(8) // BS
PORT_BIT(0x02 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_HOME) PORT_CHAR(UCHAR_MAMEKEY(HOME)) // OK
- PORT_BIT(0x04 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_BACKSLASH) PORT_CHAR('\\') PORT_CHAR('|') // OK
+ PORT_BIT(0x04 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_TILDE) PORT_CHAR('\\') PORT_CHAR('|') // OK
PORT_BIT(0x08 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_RIGHT) PORT_CHAR(UCHAR_MAMEKEY(RIGHT)) // OK
PORT_BIT(0x10 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_LCONTROL) PORT_CHAR(UCHAR_SHIFT_2) // OK
PORT_BIT(0x20 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_LEFT) PORT_CHAR(UCHAR_MAMEKEY(LEFT)) // OK
- PORT_BIT(0x40 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_CLOSEBRACE) PORT_CHAR(']') PORT_CHAR('}')
+ PORT_BIT(0x40 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_CLOSEBRACE) PORT_CHAR(']') PORT_CHAR('}') // OK
PORT_BIT(0x80 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_UP) PORT_CHAR(UCHAR_MAMEKEY(UP)) // OK
PORT_START("KEY7")
PORT_BIT(0x01 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_ESC) PORT_CHAR(UCHAR_MAMEKEY(ESC)) // OK
PORT_BIT(0x02 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_DOWN) PORT_CHAR(UCHAR_MAMEKEY(DOWN)) // OK
- PORT_BIT(0x04 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_MINUS) PORT_CHAR('_') PORT_CHAR('^')
+ PORT_BIT(0x04 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_EQUALS) PORT_CHAR('_') PORT_CHAR('^') // OK
PORT_BIT(0x08 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_LSHIFT) PORT_CHAR(UCHAR_SHIFT_1) // OK
PORT_BIT(0x10 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_LALT) PORT_CHAR(UCHAR_MAMEKEY(LALT)) // OK
PORT_BIT(0x20 , IP_ACTIVE_LOW , IPT_KEYBOARD) PORT_CODE(KEYCODE_CAPSLOCK) PORT_TOGGLE PORT_CHAR(UCHAR_MAMEKEY(CAPSLOCK))
@@ -727,9 +820,18 @@ static MACHINE_CONFIG_START(imds2 , imds2_state)
MCFG_LEGACY_FLOPPY_DRIVE_ADD(FLOPPY_0, imds2_floppy_interface)
+ MCFG_CPU_ADD("iocpio" , I8041 , IOC_XTAL_Y3)
+ MCFG_CPU_IO_MAP(pio_io_map)
+ MCFG_QUANTUM_TIME(attotime::from_hz(100))
+
MCFG_CPU_ADD("kbcpu", I8741, XTAL_3_579545MHz) /* 3.579545 MHz */
MCFG_CPU_IO_MAP(kb_io_map)
MCFG_QUANTUM_TIME(attotime::from_hz(100))
+
+ MCFG_CENTRONICS_ADD("centronics", centronics_devices, "printer")
+ MCFG_CENTRONICS_ACK_HANDLER(WRITELINE(imds2_state , imds2_pio_lpt_ack_w))
+ MCFG_CENTRONICS_BUSY_HANDLER(WRITELINE(imds2_state , imds2_pio_lpt_busy_w))
+ MCFG_CENTRONICS_PERROR_HANDLER(WRITELINE(imds2_state , imds2_pio_lpt_select_w))
MACHINE_CONFIG_END
ROM_START(imds2)
@@ -743,6 +845,13 @@ ROM_START(imds2)
ROM_LOAD("ioc_a51.bin" , 0x0800 , 0x0800 , CRC(6aa2f86c) SHA1(d3a5314d86e3366545b4c97b29e323dfab383d5f))
ROM_LOAD("ioc_a52.bin" , 0x1000 , 0x0800 , CRC(b88a38d5) SHA1(934716a1daec852f4d1f846510f42408df0c9584))
ROM_LOAD("ioc_a53.bin" , 0x1800 , 0x0800 , CRC(c8df4bb9) SHA1(2dfb921e94ae7033a7182457b2f00657674d1b77))
+
+ // ROM definition of PIO controller (8041A)
+ // For the time being a specially developped PIO firmware is used until a dump of the original PIO is
+ // available.
+ ROM_REGION(0x400 , "iocpio" , 0)
+ ROM_LOAD("pio_a72.bin" , 0 , 0x400 , BAD_DUMP CRC(8c8e740b))
+
// ROM definition of keyboard controller (8741)
ROM_REGION(0x400 , "kbcpu" , 0)
ROM_LOAD("kbd511.bin" , 0 , 0x400 , CRC(ba7c4303) SHA1(19899af732d0ae1247bfc79979b1ee5f339ee5cf))