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STEPHAN VAN DIJCK 2 minutes ago
It worked like magic! Now one last question. What do you have to do to get the backlight going on the LCD?  
Platino Soldering Station [140107 ]
Roland Härter
Roland Härter 15 hours ago
If you want to use the circuit in Europe or any other region with 230V AC line voltage, you should consider to use for example MOC3052M or MOC3063-M because MOC3020M ist only specified for 115V AC line voltage ...
230V AC dimmer, mains isolated, using P12F629
DanyR 1 day ago
Hi Gerald, Thanks for the information, I did not know such PIC's existed! Of course there is still the problem/necessity of mains isolation that is not solved using those pic's, so perhaps some extra electronics are necessary.
230V AC dimmer, mains isolated, using P12F629
Thomas Beck
Thomas Beck 1 day ago
Finally, my Adafruit 2x13 GPIO stacking headers have arrived and I could build a Pi-OBD-cube ... well, it is rather a Pi-OBD-cuboid or Pi-OBD-brick ;-) I use the stacking header to gain some space under the 3.2" touchscreen display, so that even my DXM add-on breadboard built without bent pin headers can be mounted under the display. In order to use the Pi-OBD add-on board together with displays connected via the GPIOs, a stacking header comes in handy, too. However, if using a stacking header, you might need larger spacers. I have attached images of the results below. The Pi-OBD add-on board and a cool case suitable for a Pi with the official 7" touchscreen have been released by DIAMEX in the meantime. With their permission I have added images of the final version of the Pi-OBD add-on board and the case to the main project page. If you want to use the Pi-OBD together with a display connected to the 2x13 or 2x20 GPIOs of the Pi, I suggest doing the following: desolder the 8x1 socket on the Pi-OBD add-on board or try to get a Pi-OBD add-on board from DIAMEX without it solder a 2x13 or 2x20 GPIO stacking header there After that change you can mount your display on top of the Pi-OBD add-on board. However, you have to check the data sheet of your display first if no GPIOs conflict with GPIOs used by the Pi-OBD: GPIO 14, 15, 18, 23. Assuming that no display using the SPI GPIOs actively uses the serial interface GPIOs 14 and 15 (a conflict that cannot be resolved), the relevant GPIOs to check are 18 and 23. In case of the Waveshare/Joy-it 3.2" touchscreen there is a conflict with GPIO 18 that simply can be solved. That GPIO is used by one of the 3 general purpose push buttons on the 3.2" touchscreen PCB. Pressing a button pulls the signal to ground. Since GPIO 18 is used as active low reset input by the Pi-OBD add-on board, pressing the button connected with GPIO 18 would force a reset of the Pi-OBD add-on board. However, since GPIO 18 is configured as output for the Pi, the output of the Pi could get fried if pulled to ground while being active high. Since according to the Waveshare schematics the push button is connected right to ground without using a pull down resistor, the GPIO 18 output of the Pi that is set to high by the Pi-OBD initialization script (described in the Pi-OBD manual) will be destroyed. In order to avoid that, cut the extended pin of GPIO 18 after the Pi-OBD add-on board solder joint for GPIO 18 or bend it. So that there is a connection for GPIO 18 just between the Pi and the Pi-OBD add-on board and no connection for GPIO 18 between the display and the Pi-OBD add-on board. If you have developed software that uses that push button, you could wire GPIO 18 of the display to another GPIO not used by the Pi-OBD add-on board. Of course the software using the button has to be changed, too. If a conflict for GPIOs 18 and/or 23 cannot be resolved by cutting an extended pin of the stacking header, the solution is more complicated.   the pins and the socket part of the stacking header for GPIOs 18 and/or 23 must be removed completely the contacts for GPIOs 18 and/or 23 of the Pi-OBD add-on board must be wired to other GPIOs of the Pi that are not used by the display the contacts for GPIOs 18 and/or 23 of the display must be wired to the GPIOs 18 and/or 23 of the Pi the initialization script for the Pi-OBD add-on board has to be changed to use the new GPIOs By the way, I suggest adding the commands of the Pi-OBD add-on board initialization script to the script presented on the main project page. If you use the gpio command of the Pi-OBD initialization script, you might need the full path to the gpio command if you run the script during boot time, when the PATH environment variable is not set, yet. The command which gpio returns the path (in my case /usr/bin/gpio). For the Pi-OBD and HHGui started without background image the resulting script could be like this: #!/bin/sh gpio export 18 out gpio export 23 out gpio –g write 18 0 gpio –g write 23 0 sleep 1 gpio –g write 18 1 sleep 1 /<your_path_to_hhgui>/hhgui /dev/ttyAMA0 115200 init=AGV nocursor fullscreen
OBD2 for Raspberry Pi
geralds 1 day ago
Hi Christian, the PIC16F18313 is a fine new controller, but i suggest that using a controller that have included a ZCD would be a little bit better. Best regards Gerald ---  
230V AC dimmer, mains isolated, using P12F629