USB Programming/Power Cable

R

rWAVE

Member
Greetings All,

I am designing a new board and wish to use a single USB cable to both program and power the PICAXE (I understand it is "non-standard"). Basically, I want to use a USB "A" connector at the PC end and a USB "B" connector at the PICAXE (or board) end. I am hoping to avoid building a cable.

Various Google and forum searches haven't yielded what I think I want. Although USB-A to USB-B cables are readily available, I believe I need a USB to Serial conversion within the cable.

Does such a cable exist? Or am I stuck with DIY?

Richard
 
W

womai

Senior Member
There is also a 5V version of that cable available. I use it with very good success in my new scope design (http://www.dpscope.com). You can set it up to deliver up to 500mA from the USB port. Just beware, the actual voltage may be lower than 5V, especially when running over an unpowered hub. I have seen as low as 4.3V.

You can also have it invert drive and/or receive signal so you can use it without a MAX-232 interface.

In the US you can get it from Mouser, part no. 895-TTL-232R-5V-WE

Wolfgang
 
C

ciseco

Senior Member
Sounds like you are either doing or accidentally replicating an Arduino style programming interface. Take a look at their circuits, there's very little to using an FTDI 232RL (few caps and resistors), biggest problem you'll face is trying to solder a 28 pin TSSOP on any but a proper PCB with a soldermask, so.....

The other choice is sparkfun and ebay peeps do sell USB to TTL interfaces, the ones I've seen usually have a 5v output and sometimes a low current 3.3v one too.

Cheers

Miles
________
herbalaire
 
Last edited:
J

Janne

Senior Member
I've did this on one ocassion. In the case, I put a USB-b connector to the picaxe board, and took power from the usb to picaxe. I then connected the usb signals to a cheapo 7$ usb-to-serial converter, and plugged the serial port of the converter to the picaxe hardware serial port. Worked like a dream. And programming the picaxe by the normal serial download cable via the converter also worked.
 
You must log in or register to reply here.
Top