[Howto] Raspberry Pi + I²C + MCP23017 + C (minimal example)
minimal working example: read data from MCP23017-register and print it to screen.
[Facts] Raspberry Pi + I²C + MCP23017: digital output toggle timespan (Bash, Python, C)
purpose: measuring the timespan between rising/falling-edge (=off/on/off-change) of a digital-output-bank (GPA0…GPA7) testing equipment: -Raspberry Pi 3 Modell B-I2C-adress of MCP23017-chip = 0x20-MCP23017 register-adress of 8 digital-outputs: 0x14-Owon SDS7102 digital ocsilloscope conclusion: I²C-baudrate bash Python C 100.000 5,18 ms @ 75 … Continued
[Howto] set the speed of I²C-Bus from Raspberry Pi
to set the speed you have to load the module with the corresponding option for speed (e.g. for 32k Baudrate). list the actually loaded modules: lsmod unload the i2c-module: rmmod i2c_bcm2708 load the module with the speed-option: … Continued
[Howto] use GPIO from Raspberry Pi
the Linux-Kernel manages the GPIO-system under the path /sys/class/gpio. Use the following commands to manage the pins (e.g. GPIO 17): activate GPIO 17: echo 17 > /sys/class/gpio/export deactivate GPIO 17: echo 17 > /sys/class/gpio/unexport configure GPIO 17 as … Continued
[Test] Raspberry Pi Modell B, Network Performance
Server: Raspberry Pi Modell B, 100 Mbit/s Onboard NIC with Rasbian OS running command: iperf -s Client: Core i3-4160, Supermicro X10-SAE, 1000 Mbit/s Intel NIC running command: iperf -t 30 -c 192.168.0.1 -P 25 Result: 55.4 Mbit/s