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Added the CAF Technology C747 and assorted OPTi fixes, including the implementation of OPTi 498 for the Mylex 486.

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OBattler
2025-06-14 16:33:25 +02:00
parent 8a4e8696b9
commit 5e9d48ec1b
10 changed files with 594 additions and 29 deletions
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24
src/chipset/opti895.c
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@@ -16,6 +16,7 @@
* Copyright 2008-2020 Tiseno100.
* Copyright 2016-2020 Miran Grca.
*/
#include <math.h>
#include <stdarg.h>
#include <stdint.h>
#include <stdio.h>
@@ -182,6 +183,27 @@ opti895_write(uint16_t addr, uint8_t val, void *priv)
smram_state_change(dev->smram, 0, !!(val & 0x80));
break;
case 0x25: {
double bus_clk;
switch (val & 0x03) {
default:
case 0x00:
bus_clk = cpu_busspeed / 6.0;
break;
case 0x01:
bus_clk = cpu_busspeed / 5.0;
break;
case 0x02:
bus_clk = cpu_busspeed / 4.0;
break;
case 0x03:
bus_clk = cpu_busspeed / 3.0;
break;
}
cpu_set_isa_speed((int) round(bus_clk));
break;
}
case 0xe0:
if (!(val & 0x01))
dev->forced_green = 0;
@@ -294,6 +316,8 @@ opti895_init(const device_t *info)
smram_enable(dev->smram, 0x00030000, 0x000b0000, 0x00010000, 0, 1);
cpu_set_isa_speed((int) round(cpu_busspeed / 6.0));
return dev;
}