metroboy

#include "MetroBoyLib/MetroBoyVRAM.h"

#include "metrolib/core/Dumper.h"
#include "metrolib/gameboy/MetroBoyCPU.h"
#include "metrolib/gameboy/GBConstants.h"

#include <assert.h>
#include <memory.h>

//-----------------------------------------------------------------------------
// the nintendo logo as it appears in vram

static const uint8_t bootrom_logo[] = {
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0xf0, 0x00, 0xf0, 0x00, 0xfc, 0x00, 0xfc, 0x00, 0xfc, 0x00, 0xfc, 0x00, 0xf3, 0x00, 0xf3, 0x00,
  0x3c, 0x00, 0x3c, 0x00, 0x3c, 0x00, 0x3c, 0x00, 0x3c, 0x00, 0x3c, 0x00, 0x3c, 0x00, 0x3c, 0x00,
  0xf0, 0x00, 0xf0, 0x00, 0xf0, 0x00, 0xf0, 0x00, 0x00, 0x00, 0x00, 0x00, 0xf3, 0x00, 0xf3, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xcf, 0x00, 0xcf, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x0f, 0x00, 0x0f, 0x00, 0x3f, 0x00, 0x3f, 0x00, 0x0f, 0x00, 0x0f, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xc0, 0x00, 0xc0, 0x00, 0x0f, 0x00, 0x0f, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xf0, 0x00, 0xf0, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xf3, 0x00, 0xf3, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xc0, 0x00, 0xc0, 0x00,
  0x03, 0x00, 0x03, 0x00, 0x03, 0x00, 0x03, 0x00, 0x03, 0x00, 0x03, 0x00, 0xff, 0x00, 0xff, 0x00,
  0xc0, 0x00, 0xc0, 0x00, 0xc0, 0x00, 0xc0, 0x00, 0xc0, 0x00, 0xc0, 0x00, 0xc3, 0x00, 0xc3, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xfc, 0x00, 0xfc, 0x00,
  0xf3, 0x00, 0xf3, 0x00, 0xf0, 0x00, 0xf0, 0x00, 0xf0, 0x00, 0xf0, 0x00, 0xf0, 0x00, 0xf0, 0x00,
  0x3c, 0x00, 0x3c, 0x00, 0xfc, 0x00, 0xfc, 0x00, 0xfc, 0x00, 0xfc, 0x00, 0x3c, 0x00, 0x3c, 0x00,
  0xf3, 0x00, 0xf3, 0x00, 0xf3, 0x00, 0xf3, 0x00, 0xf3, 0x00, 0xf3, 0x00, 0xf3, 0x00, 0xf3, 0x00,
  0xf3, 0x00, 0xf3, 0x00, 0xc3, 0x00, 0xc3, 0x00, 0xc3, 0x00, 0xc3, 0x00, 0xc3, 0x00, 0xc3, 0x00,
  0xcf, 0x00, 0xcf, 0x00, 0xcf, 0x00, 0xcf, 0x00, 0xcf, 0x00, 0xcf, 0x00, 0xcf, 0x00, 0xcf, 0x00,
  0x3c, 0x00, 0x3c, 0x00, 0x3f, 0x00, 0x3f, 0x00, 0x3c, 0x00, 0x3c, 0x00, 0x0f, 0x00, 0x0f, 0x00,
  0x3c, 0x00, 0x3c, 0x00, 0xfc, 0x00, 0xfc, 0x00, 0x00, 0x00, 0x00, 0x00, 0xfc, 0x00, 0xfc, 0x00,
  0xfc, 0x00, 0xfc, 0x00, 0xf0, 0x00, 0xf0, 0x00, 0xf0, 0x00, 0xf0, 0x00, 0xf0, 0x00, 0xf0, 0x00,
  0xf3, 0x00, 0xf3, 0x00, 0xf3, 0x00, 0xf3, 0x00, 0xf3, 0x00, 0xf3, 0x00, 0xf0, 0x00, 0xf0, 0x00,
  0xc3, 0x00, 0xc3, 0x00, 0xc3, 0x00, 0xc3, 0x00, 0xc3, 0x00, 0xc3, 0x00, 0xff, 0x00, 0xff, 0x00,
  0xcf, 0x00, 0xcf, 0x00, 0xcf, 0x00, 0xcf, 0x00, 0xcf, 0x00, 0xcf, 0x00, 0xc3, 0x00, 0xc3, 0x00,
  0x0f, 0x00, 0x0f, 0x00, 0x0f, 0x00, 0x0f, 0x00, 0x0f, 0x00, 0x0f, 0x00, 0xfc, 0x00, 0xfc, 0x00,
  0x3c, 0x00, 0x42, 0x00, 0xb9, 0x00, 0xa5, 0x00, 0xb9, 0x00, 0xa5, 0x00, 0x42, 0x00, 0x3c, 0x00,
};

//-----------------------------------------------------------------------------

void MetroBoyVRAM::reset() {
  memset(ram, 0, sizeof(ram));
  memcpy(ram, bootrom_logo, 416);
}

//-----------------------------------------------------------------------------

void MetroBoyVRAM::tick(int phase_total, const Req& req, Ack& ack) const {
  (void)phase_total;
  if (req.read && (req.addr >= 0x8000) && (req.addr <= 0x9FFF)) {
    ack.addr = req.addr;
    ack.data_lo = ram[req.addr & 0x1FFF];
    ack.read++;
  }
}

void MetroBoyVRAM::tock(int phase_total, const Req& req) {
  if (MB_DELTA_GH && req.write && (req.addr >= 0x8000) && (req.addr <= 0x9FFF)) {
    ram[req.addr & 0x1FFF] = uint8_t(req.data_lo);
  }
}

//-----------------------------------------------------------------------------