I've just finished designing a wireless board for Maple or Arduino, and you can see the PCB design here.
I'm sending it to fab now. Here are the basics:
- STM32L151C8: 48 pin, 64KB Flash, 10KB SRAM. This footprint is compatible with many devices in the L15x range, up to 384/32.
- SPIRIT1 RF transceiver and antenna for 433 MHz.
- "Half Shield" pin-out plus a 30-pin edge connector if you want access to everything.
- By default it runs the OpenTag/DASH7 stack, which is an ultra-low-power wireless networking stack. It can be configured in many ways. The "basic" configuration is set-up to establish an IP-like "socket based" network with autodetect and stuff like that.
At the moment, this is either a module that attaches to something like a Maple, or it is a hardware kit that you write applications for (typically in C), compile, and upload via SWD. It is capable of being a standalone Maple board, though. I would like to port libmaple to STM32L, and then to run Maple programs as tasks via the OpenTag RTOS. This latter part is a bit esoteric, but I can manage that. I can also manage the porting to STM32L, but if anyone in the community is interested, I will gladly accept any help. It will certainly speed-up things. Send me a message if you want to assist, and if I get the impression you know what you're doing I'll send you some boards :)