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core, testpico fixes

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This commit is contained in:
kub 2023-06-09 19:22:51 +00:00
parent 3d7abd6905
commit f61d0a4534
3 changed files with 33 additions and 12 deletions
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31
pico/memory.c
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@ -1039,10 +1039,24 @@ static void m68k_mem_setup(void)
static int get_scanline(int is_from_z80)
{
if (is_from_z80) {
int mclk_z80 = (z80_cyclesLeft<0 ? Pico.t.z80c_aim : z80_cyclesDone()) * 15;
int mclk_line = Pico.t.z80_scanline * 488 * 7;
while (mclk_z80 - mclk_line >= 488 * 7)
Pico.t.z80_scanline++, mclk_line += 488 * 7;
// ugh... compute by dividing cycles since frame start by cycles per line
// need some fractional resolution here, else there may be an extra line
int cycles_line = cycles_68k_to_z80(488 << 8); // cycles per line, as Q8
int cycles_z80 = (z80_cyclesLeft<0 ? Pico.t.z80c_aim:z80_cyclesDone())<<8;
int cycles = cycles_line * Pico.t.z80_scanline;
// approximation by multiplying with inverse
if (cycles_z80 - cycles >= 2*cycles_line) {
// compute 1/cycles_line, storing the result to avoid future dividing
static int cycles_line_o, cycles_line_i;
if (cycles_line_o != cycles_line)
{ cycles_line_o = cycles_line, cycles_line_i = (1<<22) / cycles_line; }
// compute lines = diff/cycles_line = diff*(1/cycles_line)
int lines = ((cycles_z80 - cycles) * cycles_line_i) >> 22;
Pico.t.z80_scanline += lines, cycles += cycles_line * lines;
}
// handle any rounding leftover
while (cycles_z80 - cycles >= cycles_line)
Pico.t.z80_scanline ++, cycles += cycles_line;
return Pico.t.z80_scanline;
}
@ -1342,7 +1356,8 @@ void PicoWrite16_32x(u32 a, u32 d) {}
static unsigned char z80_md_vdp_read(unsigned short a)
{
if ((a & 0xff00) == 0x7f00) {
z80_subCLeft(3);
static int f; f = (f&0xff) + 0x8c; // 0.6
z80_subCLeft(2+(f>>8)); // 3.3 per kabuto, but notaz' test implies 2.6 ?!?
Pico.t.z80_buscycles += 7;
switch (a & 0x0d)
@ -1368,9 +1383,10 @@ static unsigned char z80_md_bank_read(unsigned short a)
unsigned char ret;
// account for 68K bus access on both CPUs.
static int f; f = (f&0xff) + 0x4c; // 0.3
z80_subCLeft(3+(f>>8)); // 3.3 per kabuto
// don't use SekCyclesBurn(7) here since the Z80 doesn't run in cycle lock to
// the 68K. Count the stolen cycles to be accounted later in the 68k CPU runs
z80_subCLeft(3);
Pico.t.z80_buscycles += 7;
addr68k = Pico.m.z80_bank68k << 15;
@ -1413,9 +1429,10 @@ static void z80_md_bank_write(unsigned int a, unsigned char data)
unsigned int addr68k;
// account for 68K bus access on both CPUs.
static int f; f = (f&0xff) + 0x4c; // 0.3
z80_subCLeft(3+(f>>8)); // 3.3 per kabuto
// don't use SekCyclesBurn(7) here since the Z80 doesn't run in cycle lock to
// the 68K. Count the stolen cycles to be accounted later in the 68K CPU runs
z80_subCLeft(3);
Pico.t.z80_buscycles += 7;
addr68k = Pico.m.z80_bank68k << 15;