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comparison psg.c @ 2243:0d1d5dccdd28

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Initial implementation of oscilloscope debug view
author Michael Pavone <pavone@retrodev.com>
date Tue, 22 Nov 2022 17:57:02 -0800
parents 71b0cb7c34a6
children 0e927fce8941
comparison
equal deleted inserted replaced
2240:8e8db9141209 2243:0d1d5dccdd28
17 context->clock_inc = clock_div; 17 context->clock_inc = clock_div;
18 for (int i = 0; i < 4; i++) { 18 for (int i = 0; i < 4; i++) {
19 context->volume[i] = 0xF; 19 context->volume[i] = 0xF;
20 } 20 }
21 context->pan = 0xFF; 21 context->pan = 0xFF;
22 }
23
24 void psg_enable_scope(psg_context *context, oscilloscope *scope)
25 {
26 context->scope = scope;
27 static const char *names[] = {
28 "PSG #1",
29 "PSG #2",
30 "PSG #3",
31 "PSG Noise",
32 };
33 for (int i = 0; i < 4; i++)
34 {
35 context->scope_channel[i] = scope_add_channel(scope, names[i], 53693175 / context->clock_inc);
36 }
22 } 37 }
23 38
24 void psg_free(psg_context *context) 39 void psg_free(psg_context *context)
25 { 40 {
26 render_free_source(context->audio); 41 render_free_source(context->audio);
89 }; 104 };
90 105
91 void psg_run(psg_context * context, uint32_t cycles) 106 void psg_run(psg_context * context, uint32_t cycles)
92 { 107 {
93 while (context->cycles < cycles) { 108 while (context->cycles < cycles) {
109 uint8_t trigger[4] = {0,0,0,0};
94 for (int i = 0; i < 4; i++) { 110 for (int i = 0; i < 4; i++) {
95 if (context->counters[i]) { 111 if (context->counters[i]) {
96 context->counters[i] -= 1; 112 context->counters[i] -= 1;
97 } 113 }
98 if (!context->counters[i]) { 114 if (!context->counters[i]) {
99 context->counters[i] = context->counter_load[i]; 115 context->counters[i] = context->counter_load[i];
100 context->output_state[i] = !context->output_state[i]; 116 context->output_state[i] = !context->output_state[i];
117 trigger[i] = context->output_state[i];
101 if (i == 3 && context->output_state[i]) { 118 if (i == 3 && context->output_state[i]) {
102 context->noise_out = context->lsfr & 1; 119 context->noise_out = context->lsfr & 1;
103 context->lsfr = (context->lsfr >> 1) | (context->lsfr << 15); 120 context->lsfr = (context->lsfr >> 1) | (context->lsfr << 15);
104 if (context->noise_type) { 121 if (context->noise_type) {
105 //white noise 122 //white noise
112 } 129 }
113 130
114 int16_t left_accum = 0, right_accum = 0; 131 int16_t left_accum = 0, right_accum = 0;
115 uint8_t pan_left = 0x10, pan_right = 0x1; 132 uint8_t pan_left = 0x10, pan_right = 0x1;
116 133
134 int16_t value = 0;
117 for (int i = 0; i < 3; i++) { 135 for (int i = 0; i < 3; i++) {
118 if (context->output_state[i]) { 136 if (context->output_state[i]) {
119 int16_t value = volume_table[context->volume[i]]; 137 value = volume_table[context->volume[i]];
120 if (context->pan & pan_left) { 138 if (context->pan & pan_left) {
121 left_accum += value; 139 left_accum += value;
122 } 140 }
123 if (context->pan & pan_right) { 141 if (context->pan & pan_right) {
124 right_accum += value; 142 right_accum += value;
125 } 143 }
126 pan_left <<= 1; 144 pan_left <<= 1;
127 pan_right <<= 1; 145 pan_right <<= 1;
128 } 146 }
129 } 147 if (context->scope) {
148 scope_add_sample(context->scope, context->scope_channel[i], value, trigger[i]);
149 }
150 }
151 value = 0;
130 if (context->noise_out) { 152 if (context->noise_out) {
131 int16_t value = volume_table[context->volume[3]]; 153 value = volume_table[context->volume[3]];
132 if (context->pan & pan_left) { 154 if (context->pan & pan_left) {
133 left_accum += value; 155 left_accum += value;
134 } 156 }
135 if (context->pan & pan_right) { 157 if (context->pan & pan_right) {
136 right_accum += value; 158 right_accum += value;
137 } 159 }
160 }
161 if (context->scope) {
162 scope_add_sample(context->scope, context->scope_channel[3], value, trigger[3]);
138 } 163 }
139 164
140 render_put_stereo_sample(context->audio, left_accum, right_accum); 165 render_put_stereo_sample(context->audio, left_accum, right_accum);
141 166
142 context->cycles += context->clock_inc; 167 context->cycles += context->clock_inc;