gregjhogan / renesas-bootmode

serial interface library for renesas microcontrollers in boot mode

renesas-bootmode

serial interface library for renesas microcontrollers in boot mode

hardware

This library is tested using a FTDI FT232RL USB to serial adapter

(make sure you use one that can match Vcc of the microcontroller - 5V or 3.3V)

SH-2A

+---+PC+---+          +---+FTDI+---+          +---+MCU+---+
|          |          |            |          |           |
|      USB +<-------->+ USB     RX +<-------->+ TX        |
|          |          |         TX +<-------->+ RX        |
|          |          |            |          |           |
|          |          |        GND +<-------->+ GND       |
|          |          |        VCC +<----*--->+ FLMD0     |
|          |          |            |     '--->+ RESET     |
|          |          |            |          |           |
+----------+          +------------+          +-----------+

notes

• assumes MCU already has pull-up resistors on RX/TX lines
• assumes MCU already has pull-up resistor on RESET line
• momentarily set reset low then hold high to get into boot mode

V850E2

+---+PC+---+          +---+FTDI+---+          +---+MCU+---+
|          |          |            |          |           |
|      USB +<-------->+ USB     RX +<------*->+ TX/RX     |
|          |          |         TX +<---o  |  |           |
|          |          |            |  ,-|>-'  |           |
|          |          |            |  |       |           |
|          |          |        GND +<-*------>+ GND       |
|          |          |        VCC +<-------->+ FLMD0     |
|          |          |        RTS +<---|>o-->+ RESET     |
|          |          |            |          |           |
+----------+          +------------+          +-----------+

notes

• assumes MCU already has pull-up resistor on TX/RX line
• assumes MCU already has pull-up resistor on RESET line
• connect FTDI RTS line to inverter to MCU RESET line
• connect tri-state buffer
  • enable line wired to inverted FTDI TX
  • input line wired to GND
  • output line wired to TX/RX

references

Renesas Flash Programmer Sample Circuit for Programming by Using a PC’s Serial Port

renesas-bootmode's Issues

Security

What are the odds that the MCU just clears it's memory as a security feature.

Going to attempt to dump the firmware of a r5f7a0 from a Mazda EPS.