summaryrefslogtreecommitdiffstatshomepage
path: root/src/emu/machine/adc1213x.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/emu/machine/adc1213x.c')
-rw-r--r--src/emu/machine/adc1213x.c251
1 files changed, 251 insertions, 0 deletions
diff --git a/src/emu/machine/adc1213x.c b/src/emu/machine/adc1213x.c
new file mode 100644
index 00000000000..eef2493b03a
--- /dev/null
+++ b/src/emu/machine/adc1213x.c
@@ -0,0 +1,251 @@
+/*
+ ADC12130/ADC12132/ADC12138
+
+ Self-calibrating 12-bit Plus Sign Serial I/O A/D Converters with MUX and Sample/Hold
+
+ TODO:
+ - Only ADC12138 currently supported
+*/
+
+#include "driver.h"
+#include "adc1213x.h"
+
+#define MAX_ADC1213X_CHIPS 4
+
+typedef struct
+{
+ int cycle;
+ int data_out;
+ int data_in;
+ int conv_mode;
+ int auto_cal;
+ int auto_zero;
+ int acq_time;
+ int data_out_sign;
+ int mode;
+ int input_shift_reg;
+ int output_shift_reg;
+ int end_conv;
+
+ double (*input_callback)(int input);
+} ADC1213X;
+
+static ADC1213X adc1213x[MAX_ADC1213X_CHIPS];
+
+#define ADC1213X_CONV_MODE_12_MSB_FIRST 0
+#define ADC1213X_CONV_MODE_16_MSB_FIRST 1
+#define ADC1213X_CONV_MODE_12_LSB_FIRST 2
+#define ADC1213X_CONV_MODE_16_LSB_FIRST 3
+
+#define ADC1213X_ACQUISITION_TIME_6_CCLK 0
+#define ADC1213X_ACQUISITION_TIME_10_CCLK 1
+#define ADC1213X_ACQUISITION_TIME_18_CCLK 2
+#define ADC1213X_ACQUISITION_TIME_34_CCLK 3
+
+int adc1213x_do_r(int chip)
+{
+ //printf("ADC: DO\n");
+ return adc1213x[chip].data_out;
+}
+
+void adc1213x_di_w(int chip, int state)
+{
+ adc1213x[chip].data_in = state & 1;
+}
+
+static void adc1213x_convert(int chip, int channel, int bits16, int lsbfirst)
+{
+ int i;
+ int bits;
+ int input_value;
+ double input;
+
+ if (bits16)
+ fatalerror("ADC1213X: 16-bit mode not supported\n");
+
+ if (lsbfirst)
+ fatalerror("ADC1213X: LSB first not supported\n");
+
+ switch (channel)
+ {
+ case 0x8: // H L L L - CH0 (single-ended)
+ {
+ input = adc1213x[chip].input_callback(0);
+ break;
+ }
+ case 0xc: // H H L L - CH1 (single-ended)
+ {
+ input = adc1213x[chip].input_callback(1);
+ break;
+ }
+ case 0x9: // H L L H - CH2 (single-ended)
+ {
+ input = adc1213x[chip].input_callback(2);
+ break;
+ }
+ case 0xd: // H H L H - CH3 (single-ended)
+ {
+ input = adc1213x[chip].input_callback(3);
+ break;
+ }
+ case 0xa: // H L H L - CH4 (single-ended)
+ {
+ input = adc1213x[chip].input_callback(4);
+ break;
+ }
+ case 0xe: // H H H L - CH5 (single-ended)
+ {
+ input = adc1213x[chip].input_callback(5);
+ break;
+ }
+ case 0xb: // H L H H - CH6 (single-ended)
+ {
+ input = adc1213x[chip].input_callback(6);
+ break;
+ }
+ case 0xf: // H H H H - CH7 (single-ended)
+ {
+ input = adc1213x[chip].input_callback(7);
+ break;
+ }
+ default:
+ {
+ fatalerror("ADC1213X: unsupported channel %02X\n", channel);
+ }
+ }
+
+ input_value = (int)(input * 2047.0);
+
+ bits = 12;
+
+ // sign-extend if needed
+ if (adc1213x[chip].data_out_sign)
+ {
+ input_value = input_value | ((input_value & 0x800) << 1);
+ bits++;
+ }
+
+ adc1213x[chip].output_shift_reg = 0;
+
+ for (i=0; i < bits; i++)
+ {
+ if (input_value & (1 << ((bits-1) - i)))
+ {
+ adc1213x[chip].output_shift_reg |= (1 << i);
+ }
+ }
+
+ adc1213x[chip].data_out = adc1213x[chip].output_shift_reg & 1;
+ adc1213x[chip].output_shift_reg >>= 1;
+}
+
+void adc1213x_cs_w(int chip, int state)
+{
+ if (state)
+ {
+ //printf("ADC: CS\n");
+
+ if (adc1213x[chip].cycle >= 7)
+ {
+ int mode = adc1213x[chip].input_shift_reg >> (adc1213x[chip].cycle - 8);
+
+ switch (mode & 0xf)
+ {
+ case 0x0: // X X X X L L L L - 12 or 13 Bit MSB First conversion
+ {
+ adc1213x_convert(chip, (mode >> 4) & 0xf, 0, 0);
+ break;
+ }
+ case 0x1: // X X X X L L L H - 16 or 17 Bit MSB First conversion
+ {
+ adc1213x_convert(chip, (mode >> 4) & 0xf, 1, 0);
+ break;
+ }
+ case 0x4: // X X X X L H L L - 12 or 13 Bit LSB First conversion
+ {
+ adc1213x_convert(chip, (mode >> 4) & 0xf, 0, 1);
+ break;
+ }
+ case 0x5: // X X X X L H L H - 16 or 17 Bit LSB First conversion
+ {
+ adc1213x_convert(chip, (mode >> 4) & 0xf, 1, 1);
+ break;
+ }
+
+ default:
+ {
+ switch (mode)
+ {
+ case 0x08: // L L L L H L L L - Auto cal
+ {
+ adc1213x[chip].auto_cal = 1;
+ break;
+ }
+
+ case 0x0e: // L L L L H H H L - Acquisition time 6 CCLK cycles
+ {
+ adc1213x[chip].acq_time = ADC1213X_ACQUISITION_TIME_6_CCLK;
+ break;
+ }
+
+ case 0x8d: // H L L L H H L H - Data out with sign
+ {
+ adc1213x[chip].data_out_sign = 1;
+ break;
+ }
+
+ default:
+ {
+ fatalerror("ADC1213X: unknown config mode %02X\n", mode);
+ }
+ }
+ break;
+ }
+ }
+ }
+
+ adc1213x[chip].cycle = 0;
+ adc1213x[chip].input_shift_reg = 0;
+
+ adc1213x[chip].end_conv = 0;
+ }
+}
+
+void adc1213x_sclk_w(int chip, int state)
+{
+ if (state)
+ {
+ //printf("ADC: cycle %d, DI = %d\n", adc1213x[chip].cycle, adc1213x[chip].data_in);
+
+ adc1213x[chip].input_shift_reg <<= 1;
+ adc1213x[chip].input_shift_reg |= adc1213x[chip].data_in;
+
+ adc1213x[chip].data_out = adc1213x[chip].output_shift_reg & 1;
+ adc1213x[chip].output_shift_reg >>= 1;
+
+ adc1213x[chip].cycle++;
+ }
+}
+
+void adc1213x_conv_w(int chip, int state)
+{
+ adc1213x[chip].end_conv = 1;
+}
+
+int adc1213x_eoc_r(int chip)
+{
+ return adc1213x[chip].end_conv;
+}
+
+void adc1213x_init(int chip, double (*input_callback)( int input ))
+{
+ memset(&adc1213x[chip], 0, sizeof(ADC1213X));
+
+ adc1213x[chip].conv_mode = ADC1213X_CONV_MODE_12_MSB_FIRST;
+ adc1213x[chip].data_out_sign = 1;
+ adc1213x[chip].auto_cal = 0;
+ adc1213x[chip].auto_zero = 0;
+ adc1213x[chip].acq_time = ADC1213X_ACQUISITION_TIME_10_CCLK;
+
+ adc1213x[chip].input_callback = input_callback;
+}