6502/CLK
1
0
Fork 0
mirror of https://github.com/TomHarte/CLK.git synced 2024-12-26 09:29:45 +00:00
Code Issues Projects Releases Wiki Activity

Start sketching the PIT.

Browse Source
This commit is contained in:
Thomas Harte 2023-11-19 07:15:30 -05:00
parent a91449555f
commit 2b69081fff
1 changed files with 38 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

51
Machines/PCCompatible/PCCompatible.cpp
View File

@ -20,6 +20,27 @@
namespace PCCompatible {
class PIT {
public:
template <int channel> uint8_t read() {
return 0;
}
template <int channel> void write([[maybe_unused]] uint8_t value) {
}
void set_mode([[maybe_unused]] uint8_t value) {
const int channel = (value >> 6) & 3;
if(channel == 3) {
return;
}
}
private:
enum class LatchMode {
};
};
struct Registers {
public:
static constexpr bool is_32bit = false;
@ -269,6 +290,8 @@ struct Memory {
class IO {
public:
IO(PIT &pit) : pit_(pit) {}
template <typename IntT> void out([[maybe_unused]] uint16_t port, [[maybe_unused]] IntT value) {
switch(port) {
default:
@ -320,10 +343,10 @@ class IO {
printf("TODO: CGA write of %02x at %04x\n", value, port);
break;
case 0x0040: case 0x0041: case 0x0042: case 0x0043:
case 0x0044: case 0x0045: case 0x0046: case 0x0047:
printf("TODO: PIT write of %02x at %04x\n", value, port);
break;
case 0x0040: pit_.write<0>(uint8_t(value)); break;
case 0x0041: pit_.write<1>(uint8_t(value)); break;
case 0x0042: pit_.write<2>(uint8_t(value)); break;
case 0x0043: pit_.set_mode(uint8_t(value)); break;
}
}
template <typename IntT> IntT in([[maybe_unused]] uint16_t port) {
@ -332,10 +355,9 @@ class IO {
printf("Unhandled in: %04x\n", port);
break;
case 0x0040: case 0x0041: case 0x0042: case 0x0043:
case 0x0044: case 0x0045: case 0x0046: case 0x0047:
printf("TODO: PIT read from %04x\n", port);
break;
case 0x0040: return pit_.read<0>();
case 0x0041: return pit_.read<1>();
case 0x0042: return pit_.read<2>();
case 0x0060: case 0x0061: case 0x0062: case 0x0063:
case 0x0064: case 0x0065: case 0x0066: case 0x0067:
@ -348,7 +370,7 @@ class IO {
}
private:
PIT &pit_;
};
class FlowController {
@ -396,8 +418,8 @@ class ConcreteMachine:
public:
ConcreteMachine(
[[maybe_unused]] const Analyser::Static::Target &target,
[[maybe_unused]] const ROMMachine::ROMFetcher &rom_fetcher
) {
const ROMMachine::ROMFetcher &rom_fetcher
) : context(pit_) {
// This is actually a MIPS count; try 3 million.
set_clock_rate(3'000'000);
@ -451,11 +473,14 @@ class ConcreteMachine:
}
private:
PIT pit_;
struct Context {
Context() :
Context(PIT &pit) :
segments(registers),
memory(registers, segments),
flow_controller(registers, segments)
flow_controller(registers, segments),
io(pit)
{
reset();
}