#define SET_ANALOG_MODE() PA7 = 1
+#define SET_COUPLING(x)
+
+#define SET_CALIBRATION_PULSE(x)
+
+/* Toggle the 1kHz calibration pin, only accurate up to ca. 8MHz. */
+#define TOGGLE_CALIBRATION_PIN() PC2 = !PC2
+
+#define LED_CLEAR() PC0 = 1; PC1 = 1;
+#define LED_GREEN() PC0 = 1; PC1 = 0;
+#define LED_RED() PC0 = 0; PC1 = 1;
+
+#define TIMER2_VAL 500
+
+/* CTLx pin index (IFCLK, ADC clock input). */
+#define CTL_BIT 0
+
+#define OUT0 ((1 << CTL_BIT) << 4) /* OEx = 1, CTLx = 0 */
+#define OE_CTL (((1 << CTL_BIT) << 4) | (1 << CTL_BIT)) /* OEx = CTLx = 1 */
+
/* Change to support as many interfaces as you need. */
static BYTE altiface = 0;
void timer2_isr(void) __interrupt TF2_ISR
{
- /* Toggle the 1kHz calibration pin, only accurate up to ca. 8MHz. */
- PC2 = !PC2;
-
- if (ledcounter) {
- if (--ledcounter == 0) {
- /* Clear LED. */
- PC0 = 1;
- PC1 = 1;
- }
- }
+ TOGGLE_CALIBRATION_PIN();
+
+ if (ledcounter && (--ledcounter == 0))
+ LED_CLEAR();
TF2 = 0;
}
return TRUE;
}
+/**
+ * Each LSB in the nibble of the byte controls the coupling per channel.
+ *
+ * Setting PE3 disables AC coupling capacitor on CH0.
+ * Setting PE0 disables AC coupling capacitor on CH1.
+ */
+static void set_coupling(BYTE coupling_cfg)
+{
+ if (coupling_cfg & 0x01)
+ IOE |= 0x08;
+ else
+ IOE &= ~0x08;
+
+ if (coupling_cfg & 0x10)
+ IOE |= 0x01;
+ else
+ IOE &= ~0x01;
+}
+
static BOOL set_numchannels(BYTE numchannels)
{
if (numchannels == 1 || numchannels == 2) {
GPIFTCB0 = 0;
GPIFTRIG = (altiface == 0) ? 6 : 4;
- /* Set green LED, don't clear LED. */
+ /* Set green LED, don't clear LED afterwards (ledcounter = 0). */
+ LED_GREEN();
ledcounter = 0;
- PC0 = 1;
- PC1 = 0;
}
static void select_interface(BYTE alt)
} samplerates[] = {
{ 48, 0x80, 0, 3, 0, 0x00, 0xea },
{ 30, 0x80, 0, 3, 0, 0x00, 0xaa },
- { 24, 1, 0, 2, 1, 0x10, 0xca },
- { 16, 1, 1, 2, 0, 0x10, 0xca },
- { 12, 2, 1, 2, 0, 0x10, 0xca },
- { 8, 3, 2, 2, 0, 0x10, 0xca },
- { 4, 6, 5, 2, 0, 0x10, 0xca },
- { 2, 12, 11, 2, 0, 0x10, 0xca },
- { 1, 24, 23, 2, 0, 0x10, 0xca },
- { 50, 48, 47, 2, 0, 0x10, 0xca },
- { 20, 120, 119, 2, 0, 0x10, 0xca },
- { 10, 240, 239, 2, 0, 0x10, 0xca },
+ { 24, 1, 0, 2, 1, OUT0, 0xca },
+ { 16, 1, 1, 2, 0, OUT0, 0xca },
+ { 12, 2, 1, 2, 0, OUT0, 0xca },
+ { 8, 3, 2, 2, 0, OUT0, 0xca },
+ { 4, 6, 5, 2, 0, OUT0, 0xca },
+ { 2, 12, 11, 2, 0, OUT0, 0xca },
+ { 1, 24, 23, 2, 0, OUT0, 0xca },
+ { 50, 48, 47, 2, 0, OUT0, 0xca },
+ { 20, 120, 119, 2, 0, OUT0, 0xca },
+ { 10, 240, 239, 2, 0, OUT0, 0xca },
};
static BOOL set_samplerate(BYTE rate)
/* OUTPUT 0-7 */
EXTAUTODAT2 = samplerates[i].out0;
- EXTAUTODAT2 = 0x11; /* OE0=1, CTL0=1 */
- EXTAUTODAT2 = 0x11; /* OE0=1, CTL0=1 */
+ EXTAUTODAT2 = OE_CTL;
+ EXTAUTODAT2 = OE_CTL;
EXTAUTODAT2 = 0;
EXTAUTODAT2 = 0;
EXTAUTODAT2 = 0;
return TRUE;
}
+static BOOL set_calibration_pulse(BYTE fs)
+{
+ switch (fs) {
+ case 0: // 100Hz
+ RCAP2L = -10000 & 0xff;
+ RCAP2H = (-10000 & 0xff00) >> 8;
+ return TRUE;
+ case 1: // 1kHz
+ RCAP2L = -1000 & 0xff;
+ RCAP2H = (-1000 & 0xff00) >> 8;
+ return TRUE;
+ case 10: // 1kHz
+ RCAP2L = (BYTE)(-100 & 0xff);
+ RCAP2H = 0xff;
+ return TRUE;
+ case 50: // 50kHz
+ RCAP2L = (BYTE)(-20 & 0xff);
+ RCAP2H = 0xff;
+ return TRUE;
+ default:
+ return FALSE;
+ }
+}
+
/* Set *alt_ifc to the current alt interface for ifc. */
BOOL handle_get_interface(BYTE ifc, BYTE *alt_ifc)
{
{
stop_sampling();
- /* Set red LED. */
- PC0 = 0;
- PC1 = 1;
+ /* Set red LED, clear after timeout. */
+ LED_RED();
ledcounter = 1000;
/* Clear EP0BCH/L for each valid command. */
- if (cmd >= 0xe0 && cmd <= 0xe4) {
+ if (cmd >= 0xe0 && cmd <= 0xe6) {
EP0BCH = 0;
EP0BCL = 0;
while (EP0CS & bmEPBUSY);
case 0xe4:
set_numchannels(EP0BUF[0]);
return TRUE;
+ case 0xe5:
+ SET_COUPLING(EP0BUF[0]);
+ return TRUE;
+ case 0xe6:
+ SET_CALIBRATION_PULSE(EP0BUF[0]);
+ return TRUE;
}
return FALSE; /* Not handled by handlers. */
EA = 1;
/* Init timer2. */
- RCAP2L = -500 & 0xff;
- RCAP2H = (-500 & 0xff00) >> 8;
+ RCAP2L = -TIMER2_VAL & 0xff;
+ RCAP2H = (-TIMER2_VAL & 0xff00) >> 8;
T2CON = 0;
ET2 = 1;
TR2 = 1;
- RENUMERATE();
+ RENUMERATE_UNCOND();
+ PORTECFG = 0;
PORTCCFG = 0;
PORTACFG = 0;
+ OEE = 0xff;
OEC = 0xff;
OEA = 0xff;