maximum input frequency on GPIO port of nRF52840

RE: maximum input frequency on GPIO port of nRF52840

Jørgen Holmefjord — Thu, 27 Jun 2019 12:32:47 GMT

Hi,

There is no way to read GPIOs at a regular interval, other than reading the state of the pin/port in a timer interrupt. The timer runs at maximum 16 MHz, but you will not be able to sample that fast. There are two peripherals in nRF52840 that can operate on higher frequencies, high-speed SPI (SPIM3) and QSPI, both running at up to 32 MHz.

Best regards,
Jørgen

RE: maximum input frequency on GPIO port of nRF52840

awneil — Thu, 27 Jun 2019 10:14:20 GMT

I'd just have to look it up in the Product Specification.

RE: maximum input frequency on GPIO port of nRF52840

manoj008 — Thu, 27 Jun 2019 10:01:32 GMT

ok , thank you !

but can you pls tell me what is the maximum frequency that i can take as input from camera module on gpio as i can vary my pixel clock from camera module ?

RE: maximum input frequency on GPIO port of nRF52840

awneil — Thu, 27 Jun 2019 09:45:21 GMT

Have you studied the Product Specification?

I think you're going to need dedicated hardware to do that - I don't think you'll be able to bit-bang it.

Also remember that the key focus o BLE, as the name suggests, is low energy - not high speed nor large volumes of data.

But have you looked at this:

https://github.com/NordicPlayground/nrf52-ble-image-transfer-demo

RE: maximum input frequency on GPIO port of nRF52840

manoj008 — Thu, 27 Jun 2019 09:37:35 GMT

did u get my cocnern ?

RE: maximum input frequency on GPIO port of nRF52840

manoj008 — Thu, 27 Jun 2019 09:19:27 GMT

How many cycles does CPU take to read gpio port ?

What is the maximum clock for system as well as GPIO peripheral ?

RE: maximum input frequency on GPIO port of nRF52840

manoj008 — Thu, 27 Jun 2019 09:18:00 GMT

Hi pspavi,

actually i want to interface a CAMERA module with nRF52840 with DVP interface , and the maximum pixel clock the camera provides is of 32MHz . So ,is this interface possible ?

If not , what is the maximum frequency which can be given as a input on gpio pin.

How many cycles will CPU take to read this input frequency ? What is the maximum clock for sysytem as well as GPIO peripheral ?

Thanks

RE: maximum input frequency on GPIO port of nRF52840

awneil — Thu, 27 Jun 2019 09:14:24 GMT

[quote userid="74848" url="~/f/nordic-q-a/49056/maximum-input-frequency-on-gpio-port-of-nrf52840/195058"]explain me your task , what actually you want to do[/quote]

http://www.catb.org/esr/faqs/smart-questions.html#goal

RE: maximum input frequency on GPIO port of nRF52840

ps_anu — Thu, 27 Jun 2019 09:09:50 GMT

Hi, manoj

can you explain me your task , what actually you want to do ?

Best Regards ,

pavi

RE: maximum input frequency on GPIO port of nRF52840

awneil — Thu, 27 Jun 2019 09:07:56 GMT

That's not much clearer!

If you actually want to do any processing of that, then the CPU speed is going to be a (the?) limiting factor ...

RE: maximum input frequency on GPIO port of nRF52840

manoj008 — Thu, 27 Jun 2019 09:03:12 GMT

I mean ,i want to sample a clock of max 32MHz on GPIO pin . Is it possible ?

RE: maximum input frequency on GPIO port of nRF52840

awneil — Thu, 27 Jun 2019 08:59:15 GMT

What, exactly, do you mean by "capture" ?