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Ensures that the 9918 admits that it is the source of interrupts.

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This commit is contained in:
Thomas Harte 2017-11-29 21:33:43 -05:00
parent f0f149c018
commit ee84f33ab5
2 changed files with 4 additions and 10 deletions
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12
Components/9918/9918.cpp
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@ -184,8 +184,8 @@ void TMS9918::run_for(const HalfCycles cycles) {
if(column_ == 342) {
access_pointer_ = column_ = output_column_ = 0;
row_ = (row_ + 1) % frame_lines_;
if(row_ == 192) status_ |= 0x80;
// TODO: consider triggering an interrupt here.
screen_mode_ = next_screen_mode_;
switch(screen_mode_) {
// TODO: text mdoe.
@ -232,6 +232,7 @@ void TMS9918::set_register(int address, uint8_t value) {
switch(value & 7) {
case 0:
next_screen_mode_ = (next_screen_mode_ & 6) | ((low_write_ & 2) >> 1);
printf("NSM: %02x\n", next_screen_mode_);
break;
case 1:
@ -240,7 +241,7 @@ void TMS9918::set_register(int address, uint8_t value) {
next_screen_mode_ = (screen_mode_ & 1) | ((low_write_ & 0x18) >> 3);
sprites_16x16_ = !!(low_write_ & 0x02);
sprites_magnified_ = !!(low_write_ & 0x01);
reevaluate_interrupts();
printf("NSM: %02x\n", next_screen_mode_);
break;
case 2:
@ -293,15 +294,10 @@ uint8_t TMS9918::get_register(int address) {
// Reads from address 1 get the status register;
uint8_t result = status_;
status_ &= ~(0x80 | 0x20);
reevaluate_interrupts();
return result;
}
void TMS9918::reevaluate_interrupts() {
}
HalfCycles TMS9918::get_time_until_interrupt() {
HalfCycles TMS9918::get_time_until_interrupt() {
if(!generate_interrupts_) return HalfCycles(-1);
if(get_interrupt_line()) return HalfCycles(-1);

2
Components/9918/9918.hpp
View File

@ -74,8 +74,6 @@ class TMS9918 {
uint8_t text_colour_ = 0;
uint8_t background_colour_ = 0;
void reevaluate_interrupts();
HalfCycles half_cycles_into_frame_;
int column_ = 0, row_ = 0, output_column_ = 0;
int cycles_error_ = 0;