SWRZ101B December 2021 – December 2023 AM2732 , AM2732-Q1
SPI: A Data Length Error is Generated Repeatedly in Peripheral Mode When IO Loopback is Enabled
When a DLEN error is created in Peripheral mode of the SPI using nSCS pins in IO Loopback Test mode, the SPI module re-transmits the data with the DLEN error instead of aborting the ongoing transfer and stopping. This is only an issue for an IOLPBK mode peripheral in Analog Loopback configuration, when the intentional error generation feature is triggered using CTRLDLENERR (IOLPBKTSTCR.16).
After the DLEN_ERR interrupt is detected in IOLPBK mode, disable the transfers by clearing the SPIEN (bit 24) in the SPIGCR1 register and then, re-enable the transfers by resetting the SPIEN bit.