Posted by aonomus on January 5, 2010
So, I finally got my hands on the blogosphere-popularized STM8 Discovery dev board, the $8 dev board wonder. Not even the uber cheap Arduino clone clones can top that.
It seems like STMicro is working to push this tool out to people for cheap, targeted at educators, students, low budget hackers, etc (while the chip itself is aiming to be embedded in more projects, the dev board being so cheap makes it easy to work with and place in a project semi-permanently, and avoid working with a 48 pin VQFP package).
The compilers that are offered for free have a 16k memory limit (16k limit of the 32k flash on the chip itself), but nonetheless, for such a nice chip with its features, who can complain? I can see this supplanting the arduino in more complex projects, since it features more I/O, has a much lower price, and features the removable USB interface (which uses an identical microcontroller). ST even set up their own help forum, and while its not as busy as Arduino related forums, its certainly a useful resource if you have one of these.
The board itself is in 2 halves, the USB interface which uses a STM32 microcontroller, with a voltage regulator and supporting circuitry to run the board off of USB power, while at the same time being ‘detachable’ (by snapping the board along a routed out area). The actual microcontroller dev area itself has 4 headers, a jumper switch for power source, its own 16MHz clock, a capacitive touch switch, and a prototyping area with a SOIC16 footprint/breakout.
Amongst the nitty gritty features:
- 8 bit, 16MHz processor
- Power management, and watchdog features
- 32k flash (16k limit with the free compilers offered)
- 2k RAM
- SPI, UART, I2C, as well as CAN, smartcard, and IrDa support
- 48 pin packaged processor, the STM8S105xx
- 38 I/O pins, single 10-bit ADC with 10 channel multiplex and analog watchdog
More pictures (from unboxing to closeups):