16 Oct, 2013
KQLZ - Click to Rock
RS232 to Logic Converter
But maybe it's the first one you've seen that just plugs onto the of a DE-9 connector that has separate LED's for both TX and RX. I've seen too many with dual-color LED's and I don't like them because they are hard enough to see at low bit-rates. (Red with an occasional smidgen of green. Yea... Right.)
So I made these to show power (Yellow LED) and also have a separate Red/Green LED for each line from a MAX3221 level converter. Typically my clients who work on microcontroller products like them for temporary debug ports. They hook them up with clip-leads as shown below (although the adapter is delivered without).
The MAX3221 operates from +3.0V to +5.5V and is powered by the USER (not the RS232 signals).
So here it is -- available for a mere $25 assembled and tested. ;)
Feel free to email me if you'd like to buy some.