serial interface library for renesas microcontrollers in boot mode
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)
+---+PC+---+ +---+FTDI+---+ +---+MCU+---+
| | | | | |
| USB +<-------->+ USB RX +<-------->+ TX |
| | | TX +<-------->+ RX |
| | | | | |
| | | GND +<-------->+ GND |
| | | VCC +<----*--->+ FLMD0 |
| | | | '--->+ RESET |
| | | | | |
+----------+ +------------+ +-----------+
- 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
+---+PC+---+ +---+FTDI+---+ +---+MCU+---+
| | | | | |
| USB +<-------->+ USB RX +<------*->+ TX/RX |
| | | TX +<---o | | |
| | | | ,-|>-' | |
| | | | | | |
| | | GND +<-*------>+ GND |
| | | VCC +<-------->+ FLMD0 |
| | | RTS +<---|>o-->+ RESET |
| | | | | |
+----------+ +------------+ +-----------+
- 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
Renesas Flash Programmer Sample Circuit for Programming by Using a PC’s Serial Port