Serial programming

I am trying to program a MCU from the windows 10 ARM RPi 3B+. On a regular windows 10 machine, the Atmel flip programmer was used along with a USB-RS485 cable. I have no trouble opening this programmer App on the RPi.

The programming cable on the PCB has connections to 5V, GND, RS232_RX and RS232_TX. I jumpered these signals to the RPi GPIO. Where on the RPi can I connect the RESET and PSEN signals the hardware needs for programming? The RS232 connection from the flip programmer app is timing out.

Edited to add voltage levels for the PCB and RPi are both TTL. I don’t have Atmel drivers on windows arm. If the programming app won’t work, do I need my own bootloader program?

Thanks,
Priya

The mini UART driver only provides basic serial functionality. (RX/TX)

I suppose RESET and PSEN must be driven manually prior to the flashing process, as I doubt the software has any idea how to talk to the RPi GPIO driver.

There is a reset button that puts the mic in boot loader mode prior to connecting with the programmer. These signals probably aren’t used by the serial cable. I don’t know that the programmer uses them.