I need to use RT500 as a slave device of other main control chips, that is, Slave, to receive nearly 50KB data at a time.
I looked at the following routines in the SDK[interrupt/dma/callback 3 modes]
When I use a length of several hundred bytes, the interrupt or DMA interrupt can be triggered normally. But when I increase the length to 10K or even more than 20K, the interrupt becomes abnormal, sometimes appearing and sometimes not appearing.
My understanding is that RT500 has a buffer size internally, but I didn’t find any similar instructions in the code comments or the user manual.
Regarding the SPI Slave reception of longer data, is there any application manual that I can refer to?
Thanks...
Hi @mintisan,
Please help me looking into the RT500's Datasheet (i.MX RT500 Low-Power Crossover Processor), chapter 7.5 (High-Speed SPI interface):
"The actual SPI bit rate depends on the delays introduced by the external trace, the
external device, system clock (HCLK), and capacitive loading.
Excluding delays introduced by external device and PCB, the maximum supported bit
rate for SPI master mode (transmit/receive) is 50 Mbit/s.
Excluding delays introduced by external device and PCB, the maximum supported bit
rate for SPI slave mode (receive) is 50 Mbit/s and for SPI slave mode (transmit) is 35
Mbit/s."
50 Mb/s comes out to 6250 KB/s.
I hope you find this helpful.
Best regards,
Julián