Thread: Having trouble with TTL port
View Single Post
  #3   Spotlight this post!  
Unread 06-02-2004, 12:00
Gene F's Avatar
Gene F Gene F is offline
FIRST Fanatic
AKA: Gene Falendysz
#0343 (Metal in Motion)
Team Role: Engineer
  
Join Date: Mar 2002
Rookie Year: 2001
Location: Oconee County, SC
Posts: 218
Gene F is a splendid one to beholdGene F is a splendid one to beholdGene F is a splendid one to beholdGene F is a splendid one to beholdGene F is a splendid one to beholdGene F is a splendid one to beholdGene F is a splendid one to beholdGene F is a splendid one to behold
Send a message via AIM to Gene F
Re: Having trouble with TTL port
Dave,
We have an external device that responds to our sending of an STX char. When viewed with the o-scope we see our transmission on the tx line and see the device's response on the rx line. We did notice that when there is nothing connected to the rx line that looks like it is being driven close to the tx line. That is because the rx line is high impedance. once we connected it to the other device we didn't see any crosstalk. Our basic problem is that we never get the DataRdy2USART() routine to report TRUE indicating a character is in the receive buffer. Also reading the buffer without waiting for the DataRdy2USART() gives us garbage, not what the other device sent.

I too have sent an email to Innovation First. They have sent one reply but didn't solve the issue. I have sent them my code for review and am waiting on another reply. I will post again after they respond.
__________________
- Gene Falendysz