I have a software that drives an SC16IS750 in both I2C and SPI modes. The SC16IS750 works great in both modes except for one single problem. That is, "SC16IS750 does not seem to respond to software reset bit (SRESET) written to IOControl in SPI mode".
After writing 1 to this bit, all registers remain unchanged.
It does respond to the very same process in I2C mode, and registers are initialized as described in the "7.4.1 Hardware reset, Power-On Reset (POR) and software reset".
Have any information on this phenomenon?