PX41CX

[agarza]

(06-07-2023 09:40 PM)goosnarrggh Wrote:  From first hand experience, I can say that you definitely can use Microchip Studio to flash different regions using separate hex files in separate operations. But each region has to start out initially empty.

If you are trying to use Atmel/Microchip Studio to reporgram a region that was already programmed with something else previously (essentially, even one single bit within that region being non-1), then you need to erase the whole chip in order to be able to reliably reprogram anything.

If you want to selectively reprogram individual pages without erasing everything, then you'd need to move beyond Atmel/Microchip Studio, and instead start looking into controlling the Non-Volatile Memory Controller from software -- that is, writing a bootloader.

I'm not using Atmel/Microchip Studio. I'm using pymcuprog, with a Serial-UPDI adaptor. But still don't know if it's posible to erase and flash certain pages.
The help says "use -m to erase only a specified memory region (if available)"

(06-07-2023 09:40 PM)goosnarrggh Wrote:  But, to effectively use a bootloader for this sort of purpose, you would also need enough free pins to support a bidirectional communication port, such as a UART. Given what I've seen of your previous PX15C design (I bought/built one of your kits, and also studied the schematic), you don't have enough free pins to be able to do that.

You're right, the AVR128DA does not have enough pins to add UART. So I'm multiplexing the SPI and UART ports (display and serial).