*** MCP3208 Test - 2013oct23hk1453 ***
*** Before ADC values of TxBuf and RxBuf ***
Index 0 1 2
TxBuf 06 80 00
RxBuf 00 00 00
*** After ADC (Ch 2 = 1.64V, ARef = 2.49V) ***
Index 0 1 2
TxBuf 06 80 00
RxBuf ff ea 7f
*** End of Test. ***
Rx012 = ff ea 7f
Rx12 = ea 7f
Rx1 &0f = a
results in hex = a7f = decimal 2687
voltage = 2.49V * (2687 / 4096) = 2.49v * 0.656 = 1.63v
So the MCP3208 is almost perfect!
// ***********************************************************************
// Program - Fong EKG v5.0
// Function - Olimex EKG Board Evaluation
// Author - TL Fong
// Build - 2013.10.23.01
// Date - 2013oct23hkt1508
// Hardware - Olimex/CooCox/MagicBlue/WHUT/Somy LPC1114/C14/301/FN28
// Olimex EKG board (SHIELD-EKG/EMG Rev B, Bulgaria 2011)
// Software - GCC ARM 4.7, CoIDE 1.7.4, CoLinkEx 1.1, Flash Magic v7.51
// ***********************************************************************
#include "test050.h"
// ***********************************************************************
// Main Function
// ***********************************************************************
int main()
{
...
testMcp320802();
...
}
// ***********************************************************************
// End
// ***********************************************************************
// ***********************************************************************
// test050.h 2013oct23hkt1507
// ***********************************************************************
#include "led050.h"
#include "key050.h"
#include "spi050.h"
void testMcp320802() // 2013oct23
{
// *** Blink LED at P03 ***
setupGpioPinOutputLow050(PortPinArrayP03); // setup GPIO pin as output
blinkLed0501(PortPinArrayP03); // blink led
// *** Test MCP3028 ***
mcp320802();
}
...
// ***********************************************************************
// End
// ***********************************************************************
// ***********************************************************************
// spi050.h 2013oct23hkt1506
// ***********************************************************************
#include "gpio050.h"
#include "led050.h"
#include "lpc11xx_ssp.h"
#include "semihosting.h"
#include "stdio.h"
void mcp320802()
{
// *** Print title ***
printf("*** MCP3208 Test - 2013oct23hk1453 ***\n\n");
// Setup SPI0 with clock pin = P06
setUpSpi050(SCK0_PIO0_6);
// Setup SSEL0 pin = P02
setupSpiSsel();
// Setup transfer buffers TxBuf, RxBuf
#define BUFFER_SIZE 3
uint8_t TxBuf[BUFFER_SIZE];
uint8_t RxBuf[BUFFER_SIZE];
// Setup xferConfig = TxBuf, RxBuf
SSP_DATA_SETUP_Type xferConfig;
xferConfig.tx_data = (void*)TxBuf;
xferConfig.rx_data = (void*)RxBuf;
xferConfig.length = BUFFER_SIZE;
// Initialize MCP3208 Tx and Rx buffers
// *** Select input mode and channel number ***
uint8_t inputMode;
uint8_t channelNumber;
#define SINGLE_END_MODE 0x06; // bit 1 = 1
#define DIFFERENTIAL_END_MODE 0x04; // bit 1 = 0
inputMode = SINGLE_END_MODE;
channelNumber = 2;
// *** Initialize TxBuf and RxBuf ***
TxBuf[0] = inputMode | (channelNumber >> 2);
TxBuf[1] = channelNumber << 0x6;
TxBuf[2] = 0x00; // Don't care
RxBuf[0] = 0x00;
RxBuf[1] = 0x00;
RxBuf[2] = 0x00;
// *** Print TxBuf and RxBuf
char TxTitle[10];
char RxTitle[10];
strcpy(TxTitle, "TxBuf ");
strcpy(RxTitle, "RxBuf ");
// *** Before ADC ***
printf("\n*** Before ADC values of TxBuf and RxBuf *** \n\n");
printf("Index 0 1 2\n\n");
printXferBuffers(TxBuf, RxBuf, TxTitle, RxTitle);
// *** ADC once and print results ***
setSselLow();
SSP_ReadWrite(LPC_SSP0, &xferConfig, SSP_TRANSFER_POLLING);
setSselHigh();
// *** After ADC (Ch 2 = 1.64V) ***
printf("\n*** After ADC (Ch 2 = 1.64V, ARef = 2.49V) *** \n\n");
printf("Index 0 1 2\n\n");
printXferBuffers(TxBuf, RxBuf, TxTitle, RxTitle);
// *** Print End of Test ***
printf("\n*** End of Test. *** \n\n");
// *** calculate ADC results ***
uint16_t adcOutputHex;
// adcOutputHex = ((Rx_Buf[1] & 0x0f) * (2 ** 8)) + Rx_Buf[2];
adcOutputHex = ((RxBuf[1] & 0x0f) * 256) + RxBuf[2];
// *** Loop to display waveform by scope ***
uint8_t i;
for (i = 0; i < 10000000; i++)
{
delayMilliSecond(1);
setSselLow();
SSP_ReadWrite(LPC_SSP0, &xferConfig, SSP_TRANSFER_POLLING);
setSselHigh();
}
}
void printXferBuffers(uint8_t TxBuf[BUFFER_SIZE], uint8_t RxBuf[BUFFER_SIZE], char TxTitle[10], char RxTitle[10])
{
uint8_t Tx0 = TxBuf[0];
uint8_t Tx1 = TxBuf[1];
uint8_t Tx2 = TxBuf[2];
uint8_t Rx0 = RxBuf[0];
uint8_t Rx1 = RxBuf[1];
uint8_t Rx2 = RxBuf[2];
printf("%s %02x %02x %02x \n", TxTitle, Tx0, Tx1, Tx2);
printf("%s %02x %02x %02x \n", RxTitle, Rx0, Rx1, Rx2);
}
/*
*** Sample output ***
*** MCP3208 Test - 2013oct23hk1453 ***
*** Before ADC values of TxBuf and RxBuf ***
Index 0 1 2
TxBuf 06 80 00
RxBuf 00 00 00
*** After ADC (Ch 2 = 1.64V, ARef = 2.49V) ***
Index 0 1 2
TxBuf 06 80 00
RxBuf ff ea 7f
*** End of Test. ***
*/
...
// ***********************************************************************
// End
// ***********************************************************************
.END
No comments:
Post a Comment