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This commit is contained in:
Akamaki
2025-02-18 22:34:27 +09:00
parent 5314f519ad
commit a6e866c0e5
3 changed files with 20 additions and 4 deletions
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16
src/disk/hdc_esdi_mca.c
View File

@@ -1471,16 +1471,28 @@ static device_config_t
{ .type = -1 }
};
/*
Device for an IBM DBA (Direct Bus Attachment) hard disk.
The Disk BIOS is included in the System ROM.
Some models have an exclusive channel slot for the DBA hard disk.
Following IBM machines are supported:
* PS/2 model 55SX
* PS/2 model 65SX
* PS/2 model 70 type 3 (Slot #4)
* PS/2 model 70 type 4 (Slot #4)
* PS/55 model 5550-T (Slot #5)
* PS/55 model 5550-V (Slot #5)
*/
const device_t
esdi_integrated_device = {
.name = "IBM Integrated Fixed Disk Controller (MCA)",
.name = "IBM Integrated Fixed Disk and Controller (MCA)",
.internal_name = "esdi_integrated_mca",
.flags = DEVICE_MCA,
.local = ESDI_IS_INTEGRATED,
.init = esdi_init,
.close = esdi_close,
.reset = esdi_reset,
.available = NULL, /* The Disk BIOS is included in the System ROM */
.available = NULL,
.speed_changed = NULL,
.force_redraw = NULL,
.config = esdi_integrated_config

2
src/floppy/fdc.c
View File

@@ -740,7 +740,7 @@ fdc_write(uint16_t addr, uint8_t val, void *priv)
drive = real_drive(fdc, fdc->dor & 3);
fdc_update_rwc(fdc, drive, (val & 0x30) >> 4);
}
/* Bit 2: FIFO test mode (PS/55 only? This is not documented in neither the PS/2 HITR nor the 82077AA datasheet.)
/* Bit 2: FIFO test mode (PS/55 5550-S,T only. Undocumented)
The Power-on Self Test of PS/55 writes and verifies 8 bytes of FIFO buffer through I/O 3F5h.
If it fails, then floppy drives will be treated as DD drives. */
if (fdc->flags & FDC_FLAG_PS2_MCA) {

6
src/machine/m_ps2_mca.c
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@@ -1890,7 +1890,11 @@ machine_ps55_model_50t_init(const machine_t* model)
* Planar ID
* FFFAh - PS/55 model 5551-S0x, T0x (stage 1?)
* FFEEh - PS/55 model 5551-S1x, T1x (stage 2?)
* POST (P/N 38F6933) determination: FBxx -> 4 slots (error), xxEE -> 5 slots (ok), others -> 8 (error)
* Verification in BIOS P/N 38F6933: FBxx -> 4 slots (error), xxEE -> 5 slots (ok), others -> 8 (error)
*
* The only difference between S and T models is the CPU speed (16 MHz vs 20 MHz).
* The POST measures the speed, and sets a flag in the BIOS Data Area to indicate the sub model.
* The VM in 86Box runs faster than the real, so the POST always determines it as the T model.
*/
ps2.planar_id = 0xffee;
ps55_mca_board_model_50t_init();