Forum Post: LMP91200 no change in VOUT

Hi,

We are interfacing STM32 with LMP91200 via SPI

Using SPI driver we could configure the LMP91200, once we write the new value, we can read the old value of LMP91200.

Configuring pH
Write data: 0080 Read data: 8080
Configuring Pt1000
Write data: 8080 Read data: 0080
Configuring pH
Write data: 0080 Read data: 8080

But VOUT remains the same irrespective of register setting.

it gives pH output across VOUT and VOCM pins, we couldn't read ph across VOUT and GND / Pt1000 reading.