Sprinter/mame
2
0
Fork 0
mirror of https://github.com/holub/mame synced 2025-04-22 16:31:49 +03:00
Code Issues Actions Packages Projects Releases Wiki Activity

ad1848: Add support for auto-calibration

Browse Source
This commit is contained in:
Dirk Best 2024-12-13 15:11:31 +01:00
parent d62e3a328a
commit 8e5b54e650
2 changed files with 22 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

22
src/devices/sound/ad1848.cpp
View File

@ -38,6 +38,7 @@ void ad1848_device::device_start()
save_item(NAME(m_addr));
save_item(NAME(m_stat));
save_item(NAME(m_sam_cnt));
save_item(NAME(m_calibration_cycles));
save_item(NAME(m_samples));
save_item(NAME(m_count));
save_item(NAME(m_play));
@ -52,6 +53,7 @@ void ad1848_device::device_reset()
m_addr = 0;
m_stat = 0;
m_sam_cnt = 0;
m_calibration_cycles = 0;
m_samples = 0;
m_play = false;
m_irq = false;
@ -96,9 +98,17 @@ void ad1848_device::write(offs_t offset, uint8_t data)
break;
case 9:
{
// auto-calibration
if (m_mce && BIT(data, 3))
{
logerror("set auto-calibration\n");
m_regs.init |= 0x20;
m_calibration_cycles = 384;
}
m_play = (data & 1) ? true : false;
// FIXME: provide external configuration for XTAL1 (24.576 MHz) and XTAL2 (16.9344 MHz) inputs
attotime rate = m_play ? attotime::from_hz(((m_regs.dform & 1) ? 16.9344_MHz_XTAL : 24.576_MHz_XTAL)
attotime rate = (m_play || BIT(m_regs.init, 5)) ? attotime::from_hz(((m_regs.dform & 1) ? 16.9344_MHz_XTAL : 24.576_MHz_XTAL)
/ div_factor[(m_regs.dform >> 1) & 7]) : attotime::never;
m_timer->adjust(rate, 0 , rate);
m_drq_cb(m_play ? ASSERT_LINE : CLEAR_LINE);
@ -157,6 +167,16 @@ void ad1848_device::dack_w(uint8_t data)
TIMER_CALLBACK_MEMBER(ad1848_device::update_tick)
{
// auto-calibration
if (BIT(m_regs.init, 5))
{
if (--m_calibration_cycles == 0)
{
logerror("calibration finished\n");
m_regs.init &= ~0x20;
}
}
if(!m_play)
return;
switch(m_regs.dform >> 4)

1
src/devices/sound/ad1848.h
View File

@ -55,6 +55,7 @@ private:
uint16_t m_count;
uint32_t m_samples;
uint8_t m_sam_cnt;
uint16_t m_calibration_cycles;
bool m_play, m_mce, m_trd, m_irq;
devcb_write_line m_irq_cb;
devcb_write_line m_drq_cb;