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Serial bridge to Rasberry Pi Zero — Parallax Forums

Serial bridge to Rasberry Pi Zero

RaymanRayman Posts: 14,646
edited 2019-11-20 18:19 in Propeller 2
This is fun and maybe useful, if you have the UART pins from Raspberry Pi zero connected to P2 pins...

This simple program just relays I/O from the P2 pins where the UART is connected (P24,P25) in this case to the P2 pins connected to the FT231X USB to serial bridge (P62,P63).

With this going, you can see the Pi boot and then give it console commands.

You can use Parallax Serial Terminal, but PuttyExtra works a little better as it doesn't add a blank line in between each line.

You currently need FlexGui or Fastspin to compile this code.

Comments

  • JonnyMacJonnyMac Posts: 9,104
    edited 2019-11-20 19:47
    I have often thought about doing this -- the Propeller becomes a specialty hardware co-processor for the RPi. This opens up specialty IO that may be tricky to create native RPi drivers for.

    This kind of code is also useful for connecting vendor software to hardware. I did a road sign controller that uses an expensive VFD. The company provides a demo program for the standard RS-232 version, and I was using the TTL variant. No worries; I wrote code exactly like Ray has done here and used the Propeller as a bridge.
  • RaymanRayman Posts: 14,646
    The RPi brings a lot to the table for dirt cheap.

    My first goal is to use the RPi as a GPU for P2.

    I've toyed with OpenVG and it's not much different than FTDI's EVE2 in principle.
    You start a display list, add some stuff, and then end the list and display.
    Repeat as necessary.

    Plan is to send commands over the SPI port.
    But, UART may come in handy too, later, if want to add additional functions, such as WIFI or Bluetooth...
  • jmgjmg Posts: 15,173
    Yup, all of this is what makes a Pi pinout P2 module, aka P2D2Pi so compelling : just plug and go... serial connections already line up.
  • Program the PI with Ultibo (native bare metal Delphi/FreePascal programming, NO Linux or Windows OS needed) and the PI becomes simple to program user application/interface to the P2 with all the power of the PI hardware. Not having to deal with an OS is really a joy when doing custom applications.



  • RaymanRayman Posts: 14,646
    I imagine there are a thousand ways to do this...
    I've using Visual Studio to program over SSH connection in C++... It works...
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