Will nrf5340 support fast key press detect?

[nine-fox]

Hi Nordic,

I am a 52840 user, focused on keyboard pcb. I designed several keyboards using GPIOTE, matrix scanning and other techniques provided by Nordic.

However, based on my latest testing, it will lose key pressing event when over 1000hz when running under BLE stack randomly. In contrast, it works well without BLE stack. So I can only draw a conclusion that key scanning interrupts priority which works lower than BLE caused this issue.

My question is, if I switch to use nrf5340, which use network core to scan keys and application core to send BLE message, will it be improved?

Thanks very much!

yours, nine-fox

[niebert]

I think you have to do the opposite (network core is responsible for radio so you do the scanning in the application core), but it does sound like an interesting use case for the 2-core architecture.

[nine-fox]

Thanks for your reply! Yeah, another use case I forget to mention is:

52840 can not read PS/2 protocol when running BLE.

I hope 5340 can resolve this issue too

[run_ar]

Sine the ble stack with high priority timing critical operation is in the network core, you could do more or less what you like on the application mcu. If this is scanning the key matrix or bit banging ps/2 doesn't really matter. Not very familiar with the ps/2 protocol I am afraid, so not sure if you could get into trouble if you want to do both, or if one of them, scanning the matrix or ps/2 is flexible enough to let the other run at higher priority. But if I where to guess it should be ok to run them at the same time.

[nine-fox]

Thanks for your reply!