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sound/k054539.cpp: Corrected reverb RAM size and addressing. (#12856)

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Top address bit for the 32K RAM is bit 16, rather than the intuitive bit 14.
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JOTEGO 2024-10-06 16:45:50 +02:00 committed by GitHub
parent 3633adc8bd
commit b4587b38ac
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GPG Key ID: B5690EEEBB952194
2 changed files with 14 additions and 22 deletions
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35
src/devices/sound/k054539.cpp
View File

@ -25,7 +25,6 @@ k054539_device::k054539_device(const machine_config &mconfig, const char *tag, d
, flags(0)
, reverb_pos(0)
, cur_ptr(0)
, cur_limit(0)
, rom_addr(0)
, stream(nullptr)
, m_timer(nullptr)
@ -131,7 +130,7 @@ void k054539_device::sound_stream_update(sound_stream &stream, std::vector<read_
rbase[reverb_pos] = 0;
for(int ch=0; ch<8; ch++)
if(regs[0x22c] & (1<<ch)) {
if(BIT(regs[0x22c], ch)) {
unsigned char *base1 = regs + 0x20*ch;
unsigned char *base2 = regs + 0x200 + 0x2*ch;
channel *chan = channels + ch;
@ -318,11 +317,11 @@ void k054539_device::init_chip()
memset(posreg_latch, 0, sizeof(posreg_latch)); //*
flags |= UPDATE_AT_KEYON; //* make it default until proven otherwise
ram = std::make_unique<uint8_t []>(0x4000);
ram = std::make_unique<uint8_t []>(0x8000);
reverb_pos = 0;
cur_ptr = 0;
memset(&ram[0], 0, 0x4000);
memset(&ram[0], 0, 0x8000);
stream = stream_alloc(0, 2, clock() / 384);
@ -333,10 +332,9 @@ void k054539_device::init_chip()
save_item(NAME(flags));
save_item(NAME(regs));
save_pointer(NAME(ram), 0x4000);
save_pointer(NAME(ram), 0x8000);
save_item(NAME(reverb_pos));
save_item(NAME(cur_ptr));
save_item(NAME(cur_limit));
save_item(NAME(rom_addr));
save_item(NAME(m_timer_state));
@ -433,16 +431,15 @@ void k054539_device::write(offs_t offset, u8 data)
break;
case 0x22d:
if(rom_addr == 0x80)
ram[cur_ptr] = data;
cur_ptr++;
if(cur_ptr == cur_limit)
cur_ptr = 0;
if(rom_addr == 0x80) {
offs_t const addr = (cur_ptr & 0x3fff) | ((cur_ptr & 0x10000) >> 2);
ram[addr] = data;
}
cur_ptr = (cur_ptr + 1) & 0x1ffff;
break;
case 0x22e:
rom_addr = data;
cur_limit = rom_addr == 0x80 ? 0x4000 : 0x20000;
cur_ptr = 0;
break;
@ -477,7 +474,6 @@ void k054539_device::write(offs_t offset, u8 data)
void k054539_device::device_post_load()
{
cur_limit = rom_addr == 0x80 ? 0x4000 : 0x20000;
}
u8 k054539_device::read(offs_t offset)
@ -485,13 +481,10 @@ u8 k054539_device::read(offs_t offset)
switch(offset) {
case 0x22d:
if(regs[0x22f] & 0x10) {
uint8_t res = (rom_addr == 0x80) ? ram[cur_ptr] : read_byte((0x20000*rom_addr)+cur_ptr);
if (!machine().side_effects_disabled())
{
cur_ptr++;
if(cur_ptr == cur_limit)
cur_ptr = 0;
}
offs_t const addr = (cur_ptr & 0x3fff) | ((cur_ptr & 0x10000) >> 2);
uint8_t res = (rom_addr == 0x80) ? ram[ram_addr] : read_byte((0x20000*rom_addr) + cur_ptr);
if(!machine().side_effects_disabled())
cur_ptr = (cur_ptr + 1) & 0x1ffff;
return res;
} else
return 0;
@ -550,7 +543,7 @@ void k054539_device::device_reset()
{
regs[0x22c] = 0;
regs[0x22f] = 0;
memset(&ram[0], 0, 0x4000);
memset(&ram[0], 0, 0x8000);
m_timer->enable(false);
}

1
src/devices/sound/k054539.h
View File

@ -93,7 +93,6 @@ private:
int reverb_pos;
int32_t cur_ptr;
int cur_limit;
uint32_t rom_addr;
channel channels[8];