How to interface with a >16-bit SPI device?

How to interface with more than 16-bit SPI devices, like a 20-bit ADC (e.g. ADS8900B)?

All but STM32H7 have 16-bit buffers (see AN5543). Are there ways to effectively use a 'lesser' microcontroller (e.g. STM32G0 or -G4)?

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Super User

on many chips SPI is 8bit only (standard), so transfer of a 24bit number is just a 3 byte spi transfer sequence.

look at ds of the adc, most use 8bit transfers.

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Associate II

Just use the cheapest, basically ANY STM32 with SPI. It'll do for your requirements.

20-bit ADC will send data in serial manner, 3 bytes, one byte at a time on 1-bit SPI MISO bus.

Principal

If the ADC was very incompatible with MCU SPIs, they would reduce their market acceptance.

There should be something to make it easy from AD protocol design.

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