Hi Claudio,
I am also looking for procedure and commands to update firmware via ISP mode and SPI interface.
I am using LPC51U68, there are some SH_CMD_xxx commands I can use to update firmware via SPI interface, but I am not sure the detail steps, commands and flash address to use.
If you succeed in ISP mode using non-USB interface, can you share the procedure and commands used with me?
Thank you.
Best Regards,
CK