A 16-bit Tom Thumb

Thanks to the efforts of Elektor Electronics and Glyn, for the first time now a European electronics magazine supplies a complete microcontroller starter board and accompanying software CD-ROM for less than 10 pounds. We already introduced the Renesas R8C in the January issue. Now it’s time to start using it.
The low-profile PCB with pre-assembled SMD components is supplied with two pin headers that you must fit and solder yourself. That yields a complete processor module in the format of a 32-pin DIL IC. There is also space reserved on the board for a 14-way pin header, but it does not have to fitted right away because it is only needed for the E8 debugger.
The actual microcontroller (the R8C/13) is contained in the 32-pin LQPF SMD package. The marking ‘R5F21134FP#U0’ reveals that it is an R8C/13 with 16 KB of flash ROM. We selected the R8C/13 because it has the same characteristics as its ‘siblings’ (R8C/10, R8C/11 and R8C/12). The board also comes fitted with a 20-MHz crystal and the necessary capacitors, as well as several other capacitors and resistors. Altogether, this amounts to a complete microcontroller system. Once a program has been loaded, all you have to do is connect a 3.3-V or 5-V supply voltage and you’ve got a working system.
Program code can be loaded using a serial interface; no special programming hardware is necessary. That’s because the microcontroller has a debug interface and a corresponding boot program that can be used to copy the software into the flash ROM.