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Merged sweeplf into tune command

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This commit is contained in:
d18c7db 2009-07-13 11:20:29 +00:00
commit e7aee94e6a
3 changed files with 54 additions and 90 deletions
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99
armsrc/appmain.c
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@ -240,92 +240,55 @@ static int AvgAdc(int ch)
return (a + 15) >> 5;
}
void MeasureAntennaTuning(void)
{
BYTE *dest = (BYTE *)BigBuf;
int i, ptr = 0, adcval = 0, peak = 0, peakv = 0, peakf = 0;;
int vLf125 = 0, vLf134 = 0, vHf = 0; // in mV
UsbCommand c;
DbpString("Measuring antenna characteristics, please wait.");
memset(BigBuf,0,sizeof(BigBuf));
/*
* Sweeps the useful LF range of the proxmark from
* 46.8kHz (divisor=255) to 600kHz (divisor=19) and
* reads the voltage in the antenna: the result is a graph
* which should clearly show the resonating frequency of your
* LF antenna ( hopefully around 90 if it is tuned to 125kHz!)
* read the voltage in the antenna, the result left
* in the buffer is a graph which should clearly show
* the resonating frequency of your LF antenna
* ( hopefully around 95 if it is tuned to 125kHz!)
*/
void SweepLFrange()
{
BYTE *dest = (BYTE *)BigBuf;
char dummy[12];
int i, peak= 0, ptr= 0;
double freq;
// clear buffer
memset(BigBuf,0,sizeof(BigBuf));
FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_READER);
for (i=255; i>19; i--) {
FpgaSendCommand(FPGA_CMD_SET_DIVISOR, i);
SpinDelay(20);
dest[i] = (137500 * AvgAdc(ADC_CHAN_LF)) >> 18;
// Vref = 3.3V, and a 10000:240 voltage divider on the input
// can measure voltages up to 137500 mV
adcval = ((137500 * AvgAdc(ADC_CHAN_LF)) >> 10);
if (i==95) vLf125 = adcval; // voltage at 125Khz
if (i==89) vLf134 = adcval; // voltage at 134Khz
dest[i] = adcval>>8; // scale int to fit in byte for graphing purposes
if(dest[i] > peak) {
peak= dest[i];
ptr= i;
}
peakv = adcval;
peak = dest[i];
peakf = i;
ptr = i;
}
}
dummy[11]= '\0';
dummy[10]= 'z';
dummy[9]= 'H';
dummy[8]= 'k';
dummy[7]= ' ';
freq= 12000000/(ptr + 1);
for(i= 6; i > 3 ; --i) {
dummy[i]= '0' + ((int) freq) % 10;
freq /= 10;
}
dummy[3]= '.';
for(i= 2; i >= 0 ; --i) {
dummy[i]= '0' + ((int) freq) % 10;
freq /= 10;
}
DbpString("Antenna resonates at:");
DbpString(dummy);
}
void MeasureAntennaTuning(void)
{
// Impedances are Zc = 1/(j*omega*C), in ohms
#define LF_TUNING_CAP_Z 1273 // 1 nF @ 125 kHz
#define HF_TUNING_CAP_Z 235 // 50 pF @ 13.56 MHz
int vLf125, vLf134, vHf; // in mV
UsbCommand c;
// Let the FPGA drive the low-frequency antenna around 125 kHz.
FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_READER | FPGA_LF_READER_USE_125_KHZ);
SpinDelay(20);
vLf125 = AvgAdc(ADC_CHAN_LF);
// Vref = 3.3V, and a 10000:240 voltage divider on the input
// can measure voltages up to 137500 mV
vLf125 = (137500 * vLf125) >> 10;
// Let the FPGA drive the low-frequency antenna around 134 kHz.
FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 88); //134.8Khz
FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_READER | FPGA_LF_READER_USE_134_KHZ);
SpinDelay(20);
vLf134 = AvgAdc(ADC_CHAN_LF);
// Vref = 3.3V, and a 10000:240 voltage divider on the input
// can measure voltages up to 137500 mV
vLf134 = (137500 * vLf134) >> 10;
// Let the FPGA drive the high-frequency antenna around 13.56 MHz.
FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
SpinDelay(20);
vHf = AvgAdc(ADC_CHAN_HF);
// Vref = 3300mV, and an 10:1 voltage divider on the input
// can measure voltages up to 33000 mV
vHf = (33000 * vHf) >> 10;
vHf = (33000 * AvgAdc(ADC_CHAN_HF)) >> 10;
c.cmd = CMD_MEASURED_ANTENNA_TUNING;
c.ext1 = (vLf125 << 0) | (vLf134 << 16);
c.ext2 = vHf;
c.ext3 = (LF_TUNING_CAP_Z << 0) | (HF_TUNING_CAP_Z << 16);
c.ext3 = peakf | (peakv << 16);
UsbSendPacket((BYTE *)&c, sizeof(c));
}
@ -836,10 +799,6 @@ void UsbPacketReceived(BYTE *packet, int len)
case CMD_READ_MEM:
ReadMem(c->ext1);
break;
case CMD_SWEEP_LF:
SweepLFrange();
break;
case CMD_SET_LF_DIVISOR:
FpgaSendCommand(FPGA_CMD_SET_DIVISOR, c->ext1);
break;