diff options
Diffstat (limited to 'src/devices/video/huc6272.cpp')
-rw-r--r-- | src/devices/video/huc6272.cpp | 22 |
1 files changed, 12 insertions, 10 deletions
diff --git a/src/devices/video/huc6272.cpp b/src/devices/video/huc6272.cpp index 5fcef2e2a7d..5f4ec6b8c7a 100644 --- a/src/devices/video/huc6272.cpp +++ b/src/devices/video/huc6272.cpp @@ -453,8 +453,9 @@ void huc6272_device::write(offs_t offset, uint32_t data) m_adpcm.playing[i] = BIT(data, i); if (!m_adpcm.playing[i]) { - m_adpcm.input[i] = -1; + m_adpcm.input[i] = 0; m_adpcm.pos[i] = 0; + m_adpcm.nibble[i] = 32; } else { @@ -504,6 +505,8 @@ void huc6272_device::write(offs_t offset, uint32_t data) } } +// TODO: clearly written in blind faith +// (interrupt_update fns are untested by the BIOS main menu) uint8_t huc6272_device::adpcm_update(int chan) { if (!m_adpcm.playing[chan]) @@ -513,7 +516,11 @@ uint8_t huc6272_device::adpcm_update(int chan) m_adpcm.pos[chan]++; if (m_adpcm.pos[chan] >= rate) { - if (m_adpcm.input[chan] == -1) + m_adpcm.nibble[chan] += 4; + if (m_adpcm.nibble[chan] >= 32) + m_adpcm.nibble[chan] = 0; + + if (m_adpcm.nibble[chan] == 0) { m_adpcm.input[chan] = read_dword(((m_page_setting & 0x1000) << 6) | m_adpcm.addr[chan]); m_adpcm.addr[chan] = (m_adpcm.addr[chan] & 0x20000) | ((m_adpcm.addr[chan] + 1) & 0x1ffff); @@ -535,7 +542,7 @@ uint8_t huc6272_device::adpcm_update(int chan) interrupt_update(); } - if (BIT(m_adpcm.control[chan],0)) // Ring Buffer + if (BIT(m_adpcm.control[chan], 0)) // Ring Buffer { m_adpcm.addr[chan] = m_adpcm.start[chan]; } @@ -545,14 +552,9 @@ uint8_t huc6272_device::adpcm_update(int chan) return 0; } } - m_adpcm.nibble[chan] = 0; - } - else - { - m_adpcm.nibble[chan] += 4; - if (m_adpcm.nibble[chan] >= 28) - m_adpcm.input[chan] = -1; + //m_adpcm.nibble[chan] = 0; } + m_adpcm.pos[chan] = 0; } |