The periph-tester board is a small PCB used to test the https://periph.io/x/periph hardware device interface library.
The board allows simple testing of i2c, spi, 1-wire, pwm, and analog.
- Gpio can be tested by connecting two pins (preferably interrupt-capable) outside the board.
- I2C can be tested by exercising an i2c eeprom and the i2c to 1-wire interface chip.
- SPI can be tested by exercising an spi eeprom.
- 1-wire can be tested be exercising a 1-wire eeprom and a 1-wire temperature sensor.
- PWM and ADC can be tested by outputting waveforms with varying duty cycles and reading the level of a low-pass filter.
- A gpio pin is connected to the write-enable of the I2C and SPI eeproms and can be used to simulate certain errors by write-protecting the eeproms. (In hindsight this creates more pain in ensuring the pin is set correctly than it has true value...)
The recommended pin-outs for various platforms are as follows.
| Function | Raspberry Pi | C.H.I.P. | ODROID-C1 |
|---|---|---|---|
| i2c bus | pins 3&5 | TWI1 (bus 1) pins U13 9&11 |
i2ca (bus 1) pins 3&5 |
| spi bus | pins 19,21,23,24 | bus 32766 pins U14 27-30 |
bus 0 pins 19,21,23,24 |
| wr-en | pin 7 | csid0(132) pin U14-31 |
gpio83 pin 7 |
| LED | pin 31 | csid1(133) pin U14-32 |
gpio100 pin 31 |
| PWM | pwm0(34) pin U13-18 |
gpio108 pin 33 |
|
| ADC | N/C | lradc pin U14-11 |
adc.ain1 pin 37 |
| GPIO | xio-p6&p7 pins U14-19&20 ap-eint1&ap-eint3 pins U14-23&24 |
To enable SPI, see http://www.chip-community.org/index.php/Hardware_Information
- gpio-write 133 1
- periph-smoketest -v i2c-testboard -bus 1 -wc 132
- periph-smoketest -v spi-testboard -wp 132
- periph-smoketest -v onewire-testboard -i2cbus 1
- periph-smoketest -v gpio 1019 1020
- periph-smoketest -v gpio 35 193
- gpio-write 133 0
- periph-smoketest -v i2c-testboard -bus 2 -wc 83
- periph-smoketest -v spi-testboard -wp 83
- periph-smoketest -v onewire-testboard -i2cbus 1
- periph-smoketest -v gpio 104 115
- periph-smoketest -v i2c-testboard -bus 1 -wc 4
- periph-smoketest -v spi-testboard -wp 4
- periph-smoketest -v onewire-testboard -i2cbus 1
- periph-smoketest -v gpio 22 23
The PCB can be ordered from OSH park, 3 PCBs cost $3.75 incl shipping. Parts can be ordered from digikey:
- M24C08 (i2c eeprom): 497-15752-1-ND
- M95080 (spi eeprom): 497-8683-1-ND
- DS2483 (i2c 1-wire interface): DS2483R+TCT-ND
- DS2431 (1-wire eeprom): DS2431+-ND
- MAX31820 (1-wire temp sensor): MAX31820MCR+-ND
- TVS diode: CDSOD323-T03SCT-ND
- LED:
- 1.8v Zener: MMSZ4678-TPMSCT-ND
- 4.7uF cap:
- 100uF cap, 4.7k resistors, 2.2k resistor: all std 0603 parts
Total parts cost: ~$10. If you are contributing to periph and would like an assembled board, contact the author.
Thorsten von Eicken