Genicom 3400e Manual De Usuario

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Several problems can cause data loss or communication problems on the 
printer. Data loss can result in printing errors or missing field data.  

Your printer is a serial ASCII device. It communicates with the host 
through an ASCII serial communication I/O port. Hardware handshaking 
involves the use of a hardware wire. Software handshaking involves a two-
way datalink between the devices. The two devices communicate with each 
other without losing data through the use of handshaking. The printer 
sends both forms of handshaking simultaneously when the printer’s input 
buffer is full. Any loss of data can cause printing errors. 

Hardware handshaking uses pin 11 or pin 20 of the RS-232 interface to 
control data flow. When the printer is using Intermec Standard protocol, 
it holds pins 11 and 20 high when the printer is ready to receive data. The 
printer holds the pins low when the printer is in one of the following 
conditions: 

• Buffer full 

• Ribbon fault 

•  No label stock 

•  Label at strip bar 

Your printer uses XON/XOFF protocol for software handshaking. When 
the input buffer is full, the printer transmits an XOFF character. The 
XOFF character alerts the host to the fact that the printer buffer is full and 
cannot receive any more data. When the printer is ready to receive more 
data, it sends the XON character. 

The following procedure lists things to check to ensure that your printer 
and host system are communicating properly. 

1  Check the cabling from the printer to the host system. 
2  Check the interfacing of the devices that are communicating with the 

printer. 

3  Check the printer for proper electrical operation of the I/O port. 
4  Test to see that the host system is not overrunning the printer’s input 

buffers. 

5  Check to see that the data string being sent to the printer contains the 

correct information.