#ifdef DSP_CPP //counter_rate = number of samples per counter event //all rates are evenly divisible by counter_range (0x7800, 30720, or 2048 * 5 * 3) //note that rate[0] is a special case, which never triggers const uint16 DSP::counter_rate[32] = { 0, 2048, 1536, 1280, 1024, 768, 640, 512, 384, 320, 256, 192, 160, 128, 96, 80, 64, 48, 40, 32, 24, 20, 16, 12, 10, 8, 6, 5, 4, 3, 2, 1, }; //counter_offset = counter offset from zero //counters do not appear to be aligned at zero for all rates const uint16 DSP::counter_offset[32] = { 0, 0, 1040, 536, 0, 1040, 536, 0, 1040, 536, 0, 1040, 536, 0, 1040, 536, 0, 1040, 536, 0, 1040, 536, 0, 1040, 536, 0, 1040, 536, 0, 1040, 0, 0, }; inline void DSP::counter_tick() { state.counter--; if(state.counter < 0) state.counter = counter_range - 1; } //return true if counter event should trigger inline bool DSP::counter_poll(unsigned rate) { if(rate == 0) return false; return (((unsigned)state.counter + counter_offset[rate]) % counter_rate[rate]) == 0; } #endif