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[NTVDM]

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Implement VGA read mode 1.


svn path=/trunk/; revision=67541
This commit is contained in:
Aleksandar Andrejevic 2015-05-03 22:02:41 +00:00
parent 0a02a6e9b7
commit 866f04e377
1 changed files with 43 additions and 7 deletions
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50
reactos/subsystems/mvdm/ntvdm/hardware/video/vga.c
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@ -644,7 +644,9 @@ static inline DWORD VgaTranslateReadAddress(DWORD Address)
Plane = VgaGcRegisters[VGA_GC_READ_MAP_SEL_REG] & 0x03;
}
return Offset + Plane * VGA_BANK_SIZE;
/* Return the offset on plane 0 for read mode 1 */
if (VgaGcRegisters[VGA_GC_MODE_REG] & VGA_GC_MODE_READ) return Offset;
else return Offset + Plane * VGA_BANK_SIZE;
}
static inline DWORD VgaTranslateWriteAddress(DWORD Address)
@ -1900,7 +1902,7 @@ VOID VgaRefreshDisplay(VOID)
VOID NTAPI VgaReadMemory(ULONG Address, PVOID Buffer, ULONG Size)
{
DWORD i;
DWORD i, j;
DWORD VideoAddress;
PUCHAR BufPtr = (PUCHAR)Buffer;
@ -1909,13 +1911,47 @@ VOID NTAPI VgaReadMemory(ULONG Address, PVOID Buffer, ULONG Size)
/* Ignore if video RAM access is disabled */
if ((VgaMiscRegister & VGA_MISC_RAM_ENABLED) == 0) return;
/* Loop through each byte */
for (i = 0; i < Size; i++)
if (!(VgaGcRegisters[VGA_GC_MODE_REG] & VGA_GC_MODE_READ))
{
VideoAddress = VgaTranslateReadAddress(Address + i);
/* Loop through each byte */
for (i = 0; i < Size; i++)
{
VideoAddress = VgaTranslateReadAddress(Address + i);
/* Copy the value to the buffer */
BufPtr[i] = VgaMemory[VideoAddress];
}
}
else
{
/* Loop through each byte */
for (i = 0; i < Size; i++)
{
BYTE Result = 0xFF;
/* Copy the value to the buffer */
BufPtr[i] = VgaMemory[VideoAddress];
/* This should always return a plane 0 address for read mode 1 */
VideoAddress = VgaTranslateReadAddress(Address + i);
for (j = 0; j < VGA_NUM_BANKS; j++)
{
/* Don't consider ignored banks */
if (!(VgaGcRegisters[VGA_GC_COLOR_IGNORE_REG] & (1 << j))) continue;
if (VgaGcRegisters[VGA_GC_COLOR_COMPARE_REG] & (1 << j))
{
/* Comparing with 11111111 */
Result &= VgaMemory[j * VGA_BANK_SIZE + LOWORD(VideoAddress)];
}
else
{
/* Comparing with 00000000 */
Result &= ~(VgaMemory[j * VGA_BANK_SIZE + LOWORD(VideoAddress)]);
}
}
/* Copy the value to the buffer */
BufPtr[i] = Result;
}
}
/* Load the latch registers */