Kurt, Maybe it is just me but I find your description a bit unclear. What do " enabled" "disabled" "active" mean? thanks-
On Sun, Oct 6, 2019 at 10:47 AM Kurt McCullum <[email protected]> wrote: > Guys, I did some testing on my T200 to figure out the whole serial port > wiring issue. > > Test 1: > 1. Write a test application to open the serial port on the PC with > DTR/DSR and CTS/RTS disabled > 2. Go to TELCOM on the T200 > 3. STAT 98N1ENN > 4. TERM > 5. Press any key on the T200 and it freezes. > > Test 1: > 1. Write a test application to open the serial port on the PC with > CTS/RTS disabled but DTR/DSR enabled > 2. Go to TELCOM on the T200 > 3. STAT 98N1ENN > 4. TERM > 5. Press any key on the T200 and it freezes. > > Test 3: > 1. Write a test application to open the serial port on the PC with > CTS/RTS enabled but DTR/DSR disabled > 2. Go to TELCOM on the T200 > 3. STAT 98N1ENN > 4. TERM > 5. Press any key on the T200 and all data is sent to the PC and sent > back to the T200. Works perfectly. > > I Then tested to see if TELCOM is actually using RST/CTS. For this I wrote > a small application to send a large file to the T200 with Xon/Xoff turned > off. I then put a bit of code in place to see if the RTS/CTS flags were > ever changed by the T200 to tell the PC to stop sending. What I found was > that the T200 never sent a flag to the PC signaling to pause sending data > due to the buffer being full. This caused garbage on the screen. > > So, what I can conclude from all of this is that the T200 serial port > hardware MUST have the RTS/CTS active or it will freeze the hardware. But > the TELCOM application does not use those signals to halt data transfer > when the buffer is full. Instead it relies on Xon/Xoff. Hope that clears > things up a bit on the mystery of the T200 serial port. > > Kurt >
