Use SPI with LMP91200

Hi, Im interest for use a circuit por measurement , but is a big problem. Not understand how modify the SPI adress for measumement as pH meter.
This is for graduate project (Chemistry pure student) and and thanking some response.

lmp91200.pdf (1.08 MB)

There is no SPI address. Instead this transfer protocol uses a chip select pin. The device does not connect MISO. Simply connect SCK, MOSI and a chip select pin and you are ready to go.


Hello, Thanks for your response, but don´t understand the connection you propose for the device.

Could you please explain how I should do? thank you very much for your help.

Ok, here is how you connect it.

Arduino      LMP91200 (PIN)
MISO          13 SDO_DIAG Serial Data Out /Diagnostic enable
Dx            14 CSB Chip select, low active.
SCK           15 SCLK Serial Clock
MOSI          16 SDI Serial Data In

Depending on which Arduino Board you intent to use the SPI pins are some what different. Check the Arduino Product Description for your board. The Dx is any Digital Pin that you want to use as chip select (active low). For Uno they are SPI: 10 (SS), 11 (MOSI), 12 (MISO), 13 (SCK).

Please note that my previous comment about MISO was wrong. You need to connect this as well to get data from the device. Now comes the fun part; writing a device driver. Remember it is 16-bit MSB first transfer (2 bytes). Good luck!