I was given the chance by the kind folks at Element14 to select a part from their website and do a review on it. I chose the Olimexino STM32 board as it’s the next step up from the Arduino and can act similar to an Arduino. The Olimexino STM32 uses an ARM microprocessor running at 72MHz which is 4.5 times faster than the Arduino’s 16MHz. You can find the Olimexino range of products at http://au.element14.com/olimex/.
It has the following key features packed into the one board, to see more of the features click here.
- Allows 9V to 30V input
- microSD card capability
- Ability to use and recharge a Li-Ion battery
- ARM 32-bit processor with 128K flash, 20K SRAM, 12-bit ADC, 16-bit PWM, 39 I/O pins, SPI, i2C, CAN, RTC, etc
Note: The ARM micro doesn’t feature an EEPROM like AVR micros do.
As the Olimexino STM32 is based on Maple (or seems to be) we can use the Maple’s IDE (which is a re-brand of the Arduino’s IDE) to start writing and uploading code with ease, most Arduino functions have been ported to the IDE. We have the blinking LED sketch shown below.
Which blinks the green LED on the top left of the board.
I tried to read a 0.917 volt battery (shown on my multimeter) using analogRead taken every 1 second which gave me the result of 1136 which on 3.3volts gives us 0.915 which is pretty close . If you read it every 10ms there is more noise introduced in which it can read it as 1121 (0.903) or 1157 (0.932), max on both ends of the scale which was taken from 440 samples.
I decided to hook up an unregulated 12 volt adapter to the Olimexino STM32 barrel jack and measured the current being drawn was 37-39mA which is quite a bit. That’s something which needs to be taken into consideration if you ever decide to make a battery powered project. There was a buzzing noise from the power supply circuitry (when my my ear was 20cm away) when using the barrel jack with a power adapter, computer PSU or a 9V battery so just something else to keep in mind if your project will use the barrel jack and if the project will be used near your ear (e.g alarm clock).
Overall the Olimexino STM32 has a lot of features packed into one board. If you are looking for something with a bit more grunt than the Arduino, then recommend you give the Olimexino a try, it’s only $35 Ex GST which is only a few dollars more than the Arduino.