topic Re: MCF52232 QSPI 24-bit transfers in ColdFire/68K Microcontrollers and Processors

MCF52232 QSPI 24-bit transfers

miodragsm — Wed, 20 Feb 2008 23:35:27 GMT

Hi All!

I'm trying to interface ADE7758 (Energy Metering IC from Analog Devices) with MCF52232. The IC has 24-bit long registers and SPI interface. After reading referance manual for MCF52232 (MCF52235RM) and searching trough forums, I didn't find out if it is possibile to initiate 24-bit data transfers with QSPI?! The manual specifies that data transfers are 8-16 bit long with 1 bit increment. Does this mean that i can not transfer 24-bit long data with QSPI?

Regards
Miodrag

Re: MCF52232 QSPI 24-bit transfers

admin — Thu, 21 Feb 2008 02:59:51 GMT

In case of QSPI inMCF52235RM is the same as QSPI in mcf5270, you can split the desired 24-bit word to two QSPI transfers. Possibly, ADE7758 demands to keep CS active between the first and the second transfer. The split can be either 16+8 or 12+12 or 8+16 bits.

Re: MCF52232 QSPI 24-bit transfers

miodragsm — Thu, 21 Feb 2008 22:21:58 GMT

Thanks for reply.
Problem was solved by frescale tech support (very quick & proffesional, great service! ).
Long transfers (longer than 16-bit) are managed by QCR[CONT] bit.