Upgrading from MPC5777C to i.MX RT1170

[ricardofranca]

Hello,

After many happy years with the MPC55xx, 56xx and 57xx, I am looking for another MCU that I can use when the MPC5777C EOL approaches.

For the moment, I do not intend to use the S32Kxx because I am not sure they outperform the MPC5777C when using their internal memories and it seems we would get much less performance from the QSPI interface than we currently get from the EBI.

As I am looking for MCUs/MPUs with automotive qualification and automotive temperature range, the S32G family not an option for the moment. Thus, the automotive version of i.MX RT1170 looks a very interesting choice for us as it seems to combine a fast core with decent internal memory, automotive qualification and apparently good external interfaces. As I am contemplating acquiring a development board to start our evaluation, we have the following questions:

- Is there any performance comparison between the i.MX family and the MPC? I suppose the core performance is much higher, but I would like to know if internal memory latencies are on par to make the M7 core run that much faster than a PowerPC one.

- Is there any way for me to compare external RAM access latency between its SDRAM (assuming a 200MHz one) and sn asynchronous SRAM connected to the 66MHz EBI I have on the MPC5777C?

- If I am to connect the processor to an FPGA (besides an external SDRAM), would it be more advisable to use the SEMC or the FlexSPI? While the reference manual mentions the FlexSPI as suitable for the task, we wonder if we could get better performance using a bus with a wider data path.

- We took a quick look at the AN13264 and it looked like we would be able to use it as we use the MPC5777C (everything, starting from boot, running bare-metal and M4 core disabled as we do not intend to use a secondary core). Can we assume that booting the i.MX RT1170 is similar to booting the MPC5777C (in the sense that no RTOS is needed and all configurations can be done directly from the M7 core)?

- Does it have a good integration with Green Hills tools (compiler, debugger and probe V4) like the MPC5xxx do?

Thanks!

Best regards,

Ricardo

[Omar_Anguiano · Accepted solution]

Unfortunately, we don’t have a direct comparison between the two families however on this application note you can get a reference on the memories performance on RT AN12437: i.MX RT Series Performance Optimization – Application Note (nxp.com)
I will send you more detailed information for the specific RT1170.

Both modules can connect to an FPGA, the decision on which to use will depend on your application requirements.
RT1170 can run on the single M7 core as bare-metal, no need for OS to boot. 

For the Green Hills integration, I suggest you contact Green Hills directly or your distributor for more detailed information on this.

Best regards,
Omar