Hi Joachim and Bob,
Merry Christmas and happy new year.
I've been trying to communicate with ADS1230 using RPi2, Python and SPIDEV library, however it seems I don't understand the "SPI-compatible" concept properly. I read your post to Jimenez question and connecting to Arduino, however I'm still struggling with my wirings here. as Jimenez mentioned, for a common SPI interface, we need MISO, MOSI, SCLK and CS(SS). and in response you mentioned since ADS1230 is just a read-out device we don't need MOSI connection (has to left unconnected) and CS has to be grounded(?) - SPIDEV holds chip-select low anyway: spi.open(0, 0 or 1). Then SCLK and DRDY/DOUT should be connected to SCLK and MISO pins on RPi respectively. The rest of my wirings are:
DVDD, AVDD, RefP >> 5 V
DGND, CLKIN, Gain, RefN, AGND, Speed, AINN >> GND
CAPS >> connected to each other with a 220 nF cap (bridged)
AINP >> I'm using a a simple Light-dependent resistor(LDR) to provide an analog signal
If anything's wrong with my wiring so far, I'll be appreciated if you could correct me. obviously, the first question is: what about the PWDN? do I need to have a separate GPIO defined for PWDN and set it High before starting to read bytes? or I'm missing something about PWDN.
next question is, since the MOSI pin left unconnected how are we supposed to send the (dummy) bytes and initiate the byte reading (calling clocks)?
Also, datasheet says that for data retrieval, DRDY/DOUT(which is now connected to MISO pin on RPi) goes low and then SLCK shifts 20 bits data and then again MISO goes high; do I need to operate these pins (SLCK and MISO) manually (bit banging for instance)?
Thank you very much
A.
