Teledyne M300EM User Manual

13.5.9.2. Troubleshooting Analyzer/Modem or Terminal Operation 

These are the general steps for troubleshooting problems with a modem connected to a Teledyne API analyzer. 

1.  Check cables for proper connection to the modem, terminal or computer.   
2.  Check to make sure the DTE-DCE is in the correct position as described in Section 8.1.1.   
3.  Check to make sure the set up command is correct.  See Section 8.2. 
4.  Verify that the Ready to Send (RTS) signal is at logic high.  The M300E/EM sets pin 7 (RTS) to greater 

than 3 volts to enable modem transmission.   

5.  Make sure the BAUD rate, word length, and stop bit settings between modem and analyzer match.  See 

6.  Use the RS-232 test function to send “w” characters to the modem, terminal or computer.  See Section 

7.  Get your terminal, modem or computer to transmit data to the analyzer (holding down the space bar is 

one way); the green LED should flicker as the instrument is receiving data. 

8.  Make sure that the communications software or terminal emulation software is functioning properly. 

Further help with serial communications is available in a separate manual “RS-232 Programming Notes” 
Teledyne API P/N 013500000. 

 

13.5.10.  THE OPTIONAL CO

There are Two LED’s located on the CO

2

 sensor PCA. 

 

  Normal Operation: V8 is not lit – V9 is Blinking 
  Error State: Both LED’s are blinking.   

Check to make sure that the cable to the CO

2

 probe is properly connected. 

04288D DCN5752