How many UARTs I can emulate? AN4457

[wickeLine228]

There is application note AN4457 which introduce UART emulation. And it says all GPIOs can be configures as UART_TX/RX. But how many? Can I use them simultaneously?

AN4457 page 6

[Fred · Accepted solution]

Hi,

it is difficult to answer this question because it depends on your requirements and also your setup (CPU speed, number of peripherals).

This UART emulation is using Timer and DMA to manage the scheduling and data transfer.

This lowers the CPU load but requires additional peripherals (not only GPIOs).

The main interest is to add 1 virtual UART on any GPIO.

But, if you need several UART emulations running in parallel, you might need several DMA and TIM.

The CPU might also become a bottleneck to deal with the frames, not allowing the system to process several requests simultaneously at the expected pace.