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FIX: cmd_send has wrong varible definitions, leading to loss of values.

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This commit is contained in:
iceman1001 2018-01-11 21:47:27 +01:00
commit 5ea8f73547
5 changed files with 78 additions and 57 deletions
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41
armsrc/appmain.c
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@ -110,7 +110,6 @@ void DbprintfEx(uint32_t cmd, const char *fmt, ...) {
// should probably limit size here; oh well, let's just use a big buffer
char output_string[128] = {0x00};
va_list ap;
va_start(ap, fmt);
kvsprintf(fmt, output_string, 10, ap);
va_end(ap);
@ -167,21 +166,19 @@ void Dbhexdump(int len, uint8_t *d, bool bAsci) {
static int ReadAdc(int ch) {
// Note: ADC_MODE_PRESCALE and ADC_MODE_SAMPLE_HOLD_TIME are set to the maximum allowed value.
// Both AMPL_LO and AMPL_HI are very high impedance (10MOhm) outputs, the input capacitance of the ADC is 12pF (typical). This results in a time constant
// of RC = 10MOhm * 12pF = 120us. Even after the maximum configurable sample&hold time of 40us the input capacitor will not be fully charged.
// AMPL_HI is are high impedance (10MOhm || 1MOhm) output, the input capacitance of the ADC is 12pF (typical). This results in a time constant
// of RC = (0.91MOhm) * 12pF = 10.9us. Even after the maximum configurable sample&hold time of 40us the input capacitor will not be fully charged.
//
// The maths are:
// If there is a voltage v_in at the input, the voltage v_cap at the capacitor (this is what we are measuring) will be
//
// v_cap = v_in * (1 - exp(-RC/SHTIM)) = v_in * (1 - exp(-3)) = v_in * 0,95 (i.e. an error of 5%)
//
// Note: with the "historic" values in the comments above, the error was 34% !!!
// v_cap = v_in * (1 - exp(-SHTIM/RC)) = v_in * (1 - exp(-40us/10.9us)) = v_in * 0,97 (i.e. an error of 3%)
AT91C_BASE_ADC->ADC_CR = AT91C_ADC_SWRST;
AT91C_BASE_ADC->ADC_MR =
ADC_MODE_PRESCALE(63) // [was 32] ADC_CLK = MCK / ((63+1) * 2) = 48MHz / 128 = 375kHz
| ADC_MODE_STARTUP_TIME(1) // [was 16] Startup Time = (1+1) * 8 / ADC_CLK = 16 / 375kHz = 42,7us Note: must be > 20us
| ADC_MODE_SAMPLE_HOLD_TIME(15); // [was 8] Sample & Hold Time SHTIM = 15 / ADC_CLK = 15 / 375kHz = 40us
ADC_MODE_PRESCALE(63) // ADC_CLK = MCK / ((63+1) * 2) = 48MHz / 128 = 375kHz
| ADC_MODE_STARTUP_TIME(1) // Startup Time = (1+1) * 8 / ADC_CLK = 16 / 375kHz = 42,7us Note: must be > 20us
| ADC_MODE_SAMPLE_HOLD_TIME(15); // Sample & Hold Time SHTIM = 15 / ADC_CLK = 15 / 375kHz = 40us
AT91C_BASE_ADC->ADC_CHER = ADC_CHANNEL(ch);
AT91C_BASE_ADC->ADC_CR = AT91C_ADC_START;
@ -205,7 +202,7 @@ void MeasureAntennaTuning(void) {
uint8_t LF_Results[256];
uint32_t i, adcval = 0, peak = 0, peakv = 0, peakf = 0;
uint32_t vLf125 = 0, vLf134 = 0, vHf = 0; // in mV
uint32_t v_lf125 = 0, v_lf134 = 0, v_hf = 0; // in mV
memset(LF_Results, 0, sizeof(LF_Results));
LED_B_ON();
@ -229,26 +226,34 @@ void MeasureAntennaTuning(void) {
SpinDelay(20);
adcval = ((MAX_ADC_LF_VOLTAGE * AvgAdc(ADC_CHAN_LF)) >> 10);
if (i == 95)
vLf125 = adcval; // voltage at 125Khz
v_lf125 = adcval; // voltage at 125Khz
if (i == 89)
vLf134 = adcval; // voltage at 134Khz
v_lf134 = adcval; // voltage at 134Khz
LF_Results[i] = adcval >> 9; // scale int to fit in byte for graphing purposes
if(LF_Results[i] > peak) {
peakv = adcval;
peak = LF_Results[i];
peakf = i;
peak = LF_Results[i];
}
}
}
LED_A_ON();
// Let the FPGA drive the high-frequency antenna around 13.56 MHz.
FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
SpinDelay(20);
vHf = (MAX_ADC_HF_VOLTAGE * AvgAdc(ADC_CHAN_HF)) >> 10;
v_hf = (MAX_ADC_HF_VOLTAGE * AvgAdc(ADC_CHAN_HF)) >> 10;
cmd_send(CMD_MEASURED_ANTENNA_TUNING, vLf125 | (vLf134 << 16), vHf, peakf | (peakv << 16), LF_Results, 256);
uint64_t arg0 = v_lf134;
arg0 <<= 32;
arg0 |= v_lf125;
uint64_t arg2 = peakv;
arg2 <<= 32;
arg2 |= peakf;
cmd_send(CMD_MEASURED_ANTENNA_TUNING, arg0, v_hf, arg2, LF_Results, 256);
FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
LEDsoff();
}
@ -262,7 +267,7 @@ void MeasureAntennaTuningHf(void) {
while( !BUTTON_PRESS() ){
SpinDelay(20);
vHf = (MAX_ADC_HF_VOLTAGE * AvgAdc(ADC_CHAN_HF)) >> 10;
DbprintfEx(CMD_MEASURE_ANTENNA_TUNING_HF, "%u mV",vHf);
DbprintfEx(CMD_MEASURE_ANTENNA_TUNING_HF, "%u mV / %5.2f V", vHf, vHf/1000.0);
}
FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
DbpString("cancelled");