ATtiny self-clamping zigzag program connector
Related articles
- Connectorless self-clamping zigzag TAG connector
- How to burn a bootloader at the ATtiny3217 with UPDI
Reducing the size of ATtiny3217 program connector
The ATtiny3217 is ideal for very small PCBs. Normally the 6-pin FTDI connector is used for programming, but this connector is much too large. That's why I designed a miniature connector, which is the subject of this article.
Since the CTS pin is not used, this pin is used now for the the UPDI. For programming by USB with an FTDI board, you have to disconnect the CTS signal from the FTDI board.
Due to the zig-zag configuration, a pin header is not needed, see this article.
Small ATtiny self-clamping program connector
ATtiny self-clamping program adapter
Zigzag 5p ATtiny program connector
- Due to the pin spacing of 0.05" / 1.27 mm, the connector is smaller.
- The 10nF capacitor is located on the adapter board en is not needed anymore on every target board.
- Due to the zig-zag configuration, a pin header is not needed, see this article.
Zigzag 0.05" mini program connector
Too large 0.1" program connector
Zigzag 5p ATtiny program connector
5p ATtiny adapter
I made an adapter to convert the 6 pin FTDI connector to the 5p ATtiny connector.
Note: this board is for uploading sketches by FTDI. For burning the bootloader by UPDI, use the SerialUPDI-programmer board.
5p ATtiny adapter
5p ATtiny adapter
Note: the 10nF capacitor C1 is now required just once at the adapter board, instead of at each target board.
Why I have PCBs made at PCBWay
A big advantage of PCBWay is that they also provide cheap stencils. The PCBs and stencils cost $5 and $10 respectively:
Cheap PCBs and stencils from PCBWay in China
PCBs and stencils from PCBWay
The auto reset R/C values are changed
There are consequences for the auto reset circuit which is required for the serial USB interface. The used R/C values are normally 10k / 100nF, but these values are no longer usable in combination with a UPDI connector. I have figured out that 100k / 10nF works well and does not disturb the UPDI operation.
Info: Programming ATmega328 vs ATtiny3217
For the Arduino chips such as the ATmega328, two connectors are needed on a board for burning the bootloader and debugging: a 6 pin FTDI and a 6 pin ISP connector.
The ATtiny3217 typically requires 2 connectors for debugging and burning the bootloader. Note that the the bootloader is burned in a different way: with UPDI.
- FTDI: For debugging and uploading the sketch.
- UPDI: For burning the boot loader.
GitHub
Please contribute on GitHub: https://github.com/avandalen/FDTI-UPDI-connector
Links