Isolated USB Programmer - USBProg v8.4

[TJ232]

   Based on my own firmware development and programming needs I have designed a while ago a a fully isolated USB to Serial adapter for communication and also programming devices while properly protecting your USB ports and devices. Lately, thu a number of iterations, I have done some hardware changes to it to make it more compact and also fully compatible with modern MCU's, like ESP8266, etc:

   Integrated hardware Autoreset function makes it suitable for direct programming ESP8266, ESP32 and other MCU's that require it.
   If you use Arduino IDE/Platformio/etc for example with ESP8266, you will love it, as it doesn't need to press anymore RST/Prog buttons for new sketch upload! The autoreset function takes care of that, putting automatically the ESP8266 module in the right boot mode.



Original Article with description, schematics, and usage example : http://www.esp8266-projects.com/2017/05/esp8266-usb-programmer-usbprog.html

Happy breadboarding,
TJ.

[mikerj]

That's a neat design.  Is this effectively a bit bashed interface, i.e. the host software controls the low level programming protocol?  Also does the isolated side work over the usual voltage signal range 3.3v to 5v?

[TJ232]

That's a neat design.  Is this effectively a bit bashed interface, i.e. the host software controls the low level programming protocol?  Also does the isolated side work over the usual voltage signal range 3.3v to 5v?

Thank you mikerj.

I have used it industrial/harsh environments with 3.0, 3.3 and 5V targets on the isolation side without any problems.
Actually the Silicon Labs digital isolator IC has a voltage range of 2.5 V < VDD < 5.5.

It was not in the main target but it is also working nice with ESP8266 and Arduino stuff, direct programming, no more buttons to press or jumpers to set, smooth and fast programming

Programming software is on Host side. Basically you can see it as a transparent USB-to-Serial interface and you can even use it like that (Rx and Tx target Pins) for safe isolated communication with your target device.

When using as a programmer, if needed for your MCU (as ESP8266 needs for example), it brings the extra set/autoreset functions that will keeep you away from the hasle of setting jumpers and pressing buttons to go in the right BOOT mode for programming.

You can see here a firmware upload example done on a Home Automation Dev Board with ESP8266:

Also, as a comparation, the same process with a standard USB adapter