We use SL8082T and have to have different SPI slaves to use. Port-Expander, memory, Sub-GHz wireless module. All of them communicate with SPI to their host. So we have to use at least 3 chip-selects, all of them low active. SL808X offers one CS “in hardware”, but the library-functions offer “GPIO chip-selects”. As we use analogue audio and we wanted to use layout-friendly GPIOs, we tried with GPIO9 to GPIO11, default PCM ports but in MUX1 available as GPIOs.
With parameter ADL_BUS_SPI_ADDR_CS_GPIO and ADL_IO_GPIO | 9 in struct adl_busSPISettings_t we expected to have GPIO 9 as chip-select in command adl_busWrite(); With the command SPI clock and MOSI deliver their data correct - but there is no reaction at the CS line. If we use hardware chip-select (/SPI1_CS) or GPIO 1 as chip-select the function is ok. But with “higher order” GPIOs we get no low at the CS line. CS line is pulled up to 1.8V and the slave is connected via level translator LSF0204.
Firmware is 7.54
Any help appreciated.