Here is a USB development board for the P8X32A-Q44 Propeller microcontroller. It has a FT232RL USB-to-UART IC, a 3.3 LDO voltage regulator, a 5MHZ crystal, and a 64KB EEPROM. He broke-out 32 IO pins of the microcontroller to two 16pin female headers.
This is version 1.1 of this design, and version 2 is currently under development.
It’s a bit unclear from the message who did this.
That’d be this guy here,linked – The Longhorn Engineer
I can’t find a schematic for this thing. V2.0 is better. There’s no reset button. Reset buttons are nice to have on a propeller board. With a 64kB EEPROM, 32kB is user-space. I always prefer socketed DIP EEPROMs. I’ve been wanting to do one of these tiny propeller boards, but really dumbed down, no FTDI chip – for use with the Prop-Plug programming dongle.
exert from the article
The FT232 was chosen as it is really simple to use USB to Serial UART chip and is used on the official Parallax Propeller boards so I would know it would work. An I2C compatible 64K EEPROM handles the program data and can be used as on board storage.
Check Page 5 and 6 for the schematic of the board. I didn’t really change how everything is hooked up. This was mainly an exercise in how small the PDS could be made.
the pdf referred to
http://www.longhornengineer.com/images/projects/PropDevKit/propeller_proto_board.pdf