Sending 8192 bytes through twi using nRF52832

RE: Sending 8192 bytes through twi using nRF52832

RAJ@LOGI — Thu, 04 Jan 2024 12:57:55 GMT

Hello I am also facing Same issue with BMI270 but only with SPI protocol. Not able to send config file of 8192 bytes. Need help for same.

RE: Sending 8192 bytes through twi using nRF52832

s.dp — Tue, 24 Oct 2023 06:39:02 GMT

I had tried myself...unable to transfer more than 255 bytes...i need to transfer more than 255 bytes for configuring BMI270...give some example code..

RE: Sending 8192 bytes through twi using nRF52832

Jørgen Holmefjord — Tue, 24 Oct 2023 05:56:02 GMT

[quote user="s.dp"]hi i need a example for more then 255 data tx[/quote]

Have you tried to implement this yourself with the suggestions in my post?

Please create a new ticket where you describe what you have done already and the problems you are facing.

RE: Sending 8192 bytes through twi using nRF52832

s.dp — Tue, 24 Oct 2023 05:52:48 GMT

hi i need a example for more then 255 data tx

RE: Sending 8192 bytes through twi using nRF52832

Jørgen Holmefjord — Thu, 29 Jul 2021 13:18:15 GMT

Hi,

The nRF52832 has a limitation of 255-byte length (8-bits) in the MAXCNT registers for serial peripherals like TWIM, SPIM, UARTE, SPIS, etc. This limitation was brought into the nrf_drv_twi driver as a uint8_t length argument to transfer functions, when this driver was first introduced, as this supports both TWIM and (legacy) TWI peripherals.

The TWI peripheral can support longer transfers, but this requires you to update the data pointer for each byte that will be transferred. This will give you lots of interrupts and higher current consumption.

The simples solution for using the TWI peripheral for longer transfers would be to migrate to the nrfx_twi driver, which supports size_t length parameters (32-bits).

Best regards,
Jørgen