Memory partition and what it means for your firmware budget
The R5F104LFAFP#10 carries 96 KB of program flash, 12 KB of RAM, and a separate 8 KB data EEPROM block — the EEPROM is a dedicated array, not emulated in flash, so you can store calibration constants or fault logs without wearing the main program memory. At 32 MHz the RL78 core executes 16-bit instructions with a single-cycle hardware multiplier — enough throughput for a PID loop or Modbus frame parsing without a DMA offload.
Peripheral set and I/O count for a control board
48 general-purpose I/O lines plus a 12-channel 10-bit ADC and a 2-channel 8-bit DAC cover analog front-end and digital interface needs on a single chip — the CSI, I²C, LINbus, and UART/USART blocks handle sensor buses and actuator commands without external transceivers for most low-voltage links. On-chip DMA, PWM, and WDT reduce CPU overhead for periodic tasks — the PWM timers can drive a small DC motor or LED dimmer directly from the GPIO pads.
The part is ROHS3 compliant, and the RL78/G14 series has broad second-source and cross-reference coverage across the Renesas portfolio — if a BOM hedge is needed, the same package and pinout is shared with other flash-density variants in the family.