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register names

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This commit is contained in:
Wolfgang Hottgenroth 2024-03-28 17:03:56 +01:00
parent fdb524c8d4
commit 6632630303
1 changed files with 19 additions and 5 deletions
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24
sound-driver/psg.c
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@ -26,19 +26,33 @@ const uint16_t frequencyCodes[8][12] = {
#define BDIR BIT1
#define R0 0
#define CHANNEL_A_TONE_PERIOD_FINE_REG R0
#define R1 1
#define CHANNEL_A_TONE_PERIOD_COARSE_REG R1
#define R2 2
#define CHANNEL_B_TONE_PERIOD_FINE_REG R2
#define R3 3
#define CHANNEL_B_TONE_PERIOD_COARSE_REG R3
#define R4 4
#define CHANNEL_C_TONE_PERIOD_FINE_REG R4
#define R5 5
#define CHANNEL_C_TONE_PERIOD_COARSE_REG R5
#define R6 6
#define NOISE_PERIOD_REG R6
#define R7 7
#define _ENABLE_REG R7
#define R10 010
#define CHANNEL_A_AMPLITUDE_REG R10
#define R11 011
#define CHANNEL_B_AMPLITUDE_REG R11
#define R12 012
#define CHANNEL_C_AMPLITUDE_REG R12
#define R13 013
#define ENVELOPE_PERIOD_FINE_REG R13
#define R14 014
#define ENVELOPE_PERIOD_COARSE_REG R13
#define R15 015
#define ENVELOPE_SHAPE_REG R15
uint8_t psgShadowRegisters[14];
@ -96,21 +110,21 @@ void psgWrite(uint8_t address, uint8_t data) {
}
void psgWriteFrequency(uint8_t channel, uint16_t frequencyCode) {
psgWrite(R0 + (channel * 2), (frequencyCode & 0x00ff));
psgWrite(R1 + (channel * 2), ((frequencyCode >> 8) & 0x000f));
psgWrite(CHANNEL_A_TONE_PERIOD_FINE_REG + (channel * 2), (frequencyCode & 0x00ff));
psgWrite(CHANNEL_A_TONE_PERIOD_COARSE_REG + (channel * 2), ((frequencyCode >> 8) & 0x000f));
}
void psgPlayTone(uint8_t channel, t_octave octave, t_note note) {
if (note == e_Pause) {
psgWrite(R7, psgReadShadow(R7) | (1 << channel));
psgWrite(_ENABLE_REG, psgReadShadow(_ENABLE_REG) | (1 << channel));
} else {
psgWrite(R7, psgReadShadow(R7) & ~(1 << channel));
psgWrite(_ENABLE_REG, psgReadShadow(_ENABLE_REG) & ~(1 << channel));
psgWriteFrequency(channel, frequencyCodes[octave][note]);
}
}
void psgAmplitude(uint8_t channel, uint8_t volume) {
psgWrite(R10 + channel, volume);
psgWrite(CHANNEL_A_AMPLITUDE_REG + channel, volume);
}
void psgInit() {