This shield is used to flash my Arduino Pro Mini with OptiBoot bootloader and to upload sketch to it. Optiboot is less Flash consuming than classic one.
Also, for 3V3 at 8MHz devices, upload at 57600 is slow, so I'm using 250KBPS upload. You can see here why and how to. So, I can upload faster and more than that, Optiboot is using 0.5K of flash instead of 2K, it's a double win configuration, especially with huge sketch like LoraWan device with LMIC stack for my Mini LORA Board.
Features
- ICSP 6 pins connector
- FTDI 6 pins connector
- Power LED
- Reset button
Got V1.0 Boards from PCBs.io. I tested them, all is fine
Nothing special to say, it's just some wiring, ICSP pins for programming (Power+SPI+Reset), FTDI (Power+Reset+RX+TX) for flashing and a LED to power the board (see if ICSP connector is fitted with good pining)
I'm using 2 PCB boards stacked with pogo pins and this avoid soldering any headers to the Mini Boards.
Click on image to zoom
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You can order PCB at PCBs.io. PCBs.io give me reward when you order my designed boards from their site. This is pretty good, because I can use these rewards to create and design new boards and order boards for a discounted price and share new boards. So if you don't care about PCB manufacturer please use PCBs.io.
Populated
With Arduino Pro Mini on it
I've compiled some bootloaders for you, use the one you prefer, I'm using:
- optiboot_flash_atmega328p_250000_8MHZ.hex (250KBPS) on 3V3 8MHz Mini
- optiboot_flash_atmega328p_250000_16MHZ.hex on 5V 16MHz Mini
I tested the 1MB ones, works fine also, here below the configuration of Fuses and Lockbit I'm using.
Fuse configuration
Lockbit
If you want to do commercial stuff with this project, please contact CH2i company so we can organize an simple agreement.
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