[GreenKeys] Interest in a flexible USB-currentloop adapter?

[epvgk at limpoc.com]

Hi folks - 

I'm trying to gauge interest in a usb-serial adapter for talking to teletypes.  I have 
a prototype and software, and if there's interest I can look into having a few made.
This would be an alternative to the CP2102 based setup some of us are using.

Full duplex optically-isolated 60mA loop interface that looks like a USB serial port 
to the computer.  does NOT include loop supply!  (may work on 20mA, but 5 bit only)

board approximately 1.5" by 2" with screw terminal blocks for loop connection and 
mini-USB socket for computer. 

Configurable from the computer - push a button on the board and it goes into config
mode, where you converse with it using a serial terminal program: 

  * arbitrary baud rate from basically 0 to the limit of the optoisolator, 
    which is probably ~300baud. 

  * Either transparent passthru mode for use with HeavyMetal or BaudotRSS, or, 

  * Translation mode, which does bidirectional 5-level to ASCII conversion, with
    LTRS/FIGS tracking, configurable CR/LF, auto-CR, unshift-on-space, and maybe 
    configurable translation tables. 
 
(or you can reflash the cpu with your own code, if you want) 

I'm hoping a per-unit cost of under $40 would cover parts and assembly, but it would 
depend on volume, etc.. I'm not hand-assembling this one, I've had enough of that :) 

eric


PS if anyone knows of a friendly, low-overhead storefront type site to handle the money
and order-taking for something like this, please let me know.