Dear All,
Running on TI MSP430, a sigma-delta AD design, read a signal from UART RX, do SD AD, and then output to UART TX.
Setup: UART is 9620 baudrate.
1 bit Sigma-delta AD. Switched-capacitor input. load capacitor 14pF ( need to change? ) 1.2V reference voltage ( provided by internal )Here is partial code: ///////////////////////////////////// ... unsigned int RXTXData,results; ....
while (1) { RX_Ready(); // UART ready to RX one Byte _BIS_SR(CPUOFF + GIE); // Enter LPM0 Until character RXed
SD16CCTL0 |= SD16SC; // Set bit to start conversion while ((SD16CCTL0 & SD16IFG)==0); // Poll interrupt flag results = SD16MEM0; // Save CH0 results (clears IFG) _NOP();
if (results >32767) { results=results-32767; RXTXData=results/26.214; } if (results == 32767) { RXTXData=0; } if (results