IBM 4613 ユーザーズマニュアル

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SurePOS 100 Technical Reference 
 
 
 
 
 
 
 
Page 33 of 104 
 
9.3.1.2 Mechanical 
Error 
Immediately after a mechanical error occurs, the printer logic drops DTR.  
 
9.3.2 
XON/XOFF Mode 
This mode is enabled after the application program transmits the ESC command to the printer. The print 
buffer must be empty or this command is ignored.  
Figure 3-7. XON/XOFF DTR Signal Timing 
 
 
 
After transmission of the ESC command, the printer outputs an XON (DC1 by control code; 11h by 
hexadecimal data) to the system. When the application program receives the XON signal, it can transmit 
data to the printer. If the data text is not sent from the application program, the printer logic outputs an 
XON signal at 3 second intervals until the printer receives data.  
The printer starts sending XOFF (DC3, 13h) when the empty space in the buffer reduces below 256 
bytes. When the application receives the XOFF signal, it halts output of data. However, the printer logic 
can continue receiving data until the buffer becomes completely full.  
Output of the XON signal is resumed when the data in the buffer is printed out and drops to below 256 
bytes.  
Figure 3-8. XON/XOFF Data Buffer 
 
 
 
Figure 3-9. XON/XOFF Status Byte