Hi post following the forum topic: (1) R7FA2L1A92DFM: Programming connector - MD pin and RES pin related query. - Forum - RA MCU - Renesas Engineering Community
I did understand the MD (P201) is a boot mode selector pin that when set to GND and MCU reset results in SCI or USB boot mode selection. Here are my queries (Could not reply back in the same thread).
1. If JTAG/SWD Pins are disabled by the user still, can we enter boot mode to upload binary?
2. What determines if Boot mode will come up as SCI mode or USB-CDC mode as I want to fix the mode to USB-CDC?
3. Does Renesas has any flashing tool for PC or any python script that helps in uploading the binary to the flash via USB-CDC so that we do not need to develop such a tool as on a high level I understood that programming is not a simple UART we need to make boot loader understandable packets, seems a tedious job?
4. I see that the on board JLink circuit connects MD pin as well may I know what is the reason for it? Does SWD/JTAG has any dependency on that pin?
5. Where is the bootloader code stored in the flash? Is it part of the memory map? Can any way that part of the code be modified by JTAG?
I would like to understand this part well:
In my system I have a HOCO as 24MHz which is a multiple of 48MHz. Dost that mean that it would be able to boot to USB-CDC?
This part is not from the document for RA4M2 but for other RA devices. The boot firmware document for RA4M2 is:
https://www.renesas.com/us/en/document/apn/standard-boot-firmware-ra-family-mcus-based-arm-cortex-m33