RE: Scalable Image Capturing Solution on the nRF52840

ovrebekk — Mon, 20 May 2019 08:31:16 GMT

I don't see any reason why this shouldn't work, assuming you can meet your cost target when adding the external memory and the parallel to serial chip.

When you mention using Serial Port #1 on the nRF52840 I assume you are talking about one of the SPI interfaces, rather than using the UART?

One thing you might want to consider since you are using the nRF52840 is to find a memory module that supports the QSPI interface. This is a 4-pin parallel interface that allows you to speed up communication with external memory, as well as run code directly from an external device (XIP, or execute in place).

The again SPI is not a bad option either, and on the nRF52840 there is a high speed SPI master interface that can go up to 32MHz clock for better throughput (the other SPI masters go to 8MHz maximum).

It should also be possible to connect directly to the parallel interface of the OV2640 to remove the need for a parallel to serial chip, but this will require you to bit bang the parallel interface. This means higher CPU utilization, and more complex software, to manually read out the data from the image sensor. Depending on your production targets this might be a worth while exercise (reducing per unit cost at the expense of a longer development cycle), but I don't have any experience with this method myself.

Best regards
Torbjørn