Author Topic: Voltage Level Issues  (Read 2040 times)

GlennP

  • Frequent Contributor
  • ****
  • Posts: 139
Voltage Level Issues
« on: February 05, 2015, 08:01:31 am »
Hi,
I am trying to get a test procedure for some boards that have been tested (rougly!) but are known to be working working from a JPeg I was given I have strapped two boards together (they are IrDA) and the idea was send a string from one to the other, this does not work(!), I went to the circuit diagram and found a TFDU4101 IrDA and a 74LG214 Schmitt trigger but no buffer to bring the logic levels to RS232.  In the photo there does not appear to be a buffer could a TTL to USB convertor have used ? 
Glenn (long time no see!) ;D

Jan Axelson

  • Administrator
  • Frequent Contributor
  • *****
  • Posts: 2597
    • Lakeview Research
Re: Voltage Level Issues
« Reply #1 on: February 05, 2015, 09:40:14 am »
TTL voltages will work over short distances (up to a few feet). If you want to use USB, one of the boards will need to function as a USB host, and the other, as a USB device.