It was a good turnout for the open workshop at PNCA on Sunday. Don and Monty both got their hot plate systems up and running and soldered some boards. A couple of others started to put together their temperature controller boards and some questions came up about things I may not have made clear enough before:
- The output signal labeled RESET is currently programmed to return the controller to the initial conditions if you ground it. This is intended to be a quick way to reset the temperature once the reflow process is completed.
- If you don't use the thermocouple interface chip, then you also don't need the bypass capacitor C4.
- C3 on the bottom of the board is used to set up the AVR reset signal for auto reset during boot loader based programming. If you use a Benito or other MCU based serial programmer, then you should solder bridge or jumper the C3 pads. If you use a plain USB to serial cable (like an FTDI based cable) then you need to solder on a .1uF capacitor for C3. The pads will accommodate either an 0603 or 0805 sized cap.