Prevention Hosts From Data Transfer Time-Out; Interface Selection; Printer Language And Control Codes - Epson Stylus COLOR 1520 Service Manual

EPSON Stylus COLOR 1520

1.3.4 Prevention Hosts from Data Transfer Time-out

Generally, hosts abandon data transfer to peripherals when a peripheral is in the busy state for dozens of
seconds continuously. To prevent hosts from this kind of time-out, the printer receives data very slowly,
several bytes par minute, even the printer is in busy state. This slowdown starts when the rest of input
buffer drops under several hundreds of bytes. Finally, the printer is in the busy state continuously when
the input buffer is full.

1.3.5 Interface Selection

The EPSON Stylus COLOR 1520 has three types of interface available :Parallel, Serial, and optional
interfaces. Each interface can be selected manually or automatically. Both modes are selected thorough
the default setting mode.


Manual selection
The interface selected through the default setting mode always prints out data from the host.


Automatic selection
When the printer is in this mode, the printer is initialized to the idle state when it is turned on. Then
the interface that receives data first will print. When the host stops data transfer and the printer is in
the stand-by state for the specific time, the printer returns to the idle state. As long as the host sends
data or the printer interface is buy state, the selected interface remains active.
Interface State and Interface Selection
When the parallel interface is not selected, the interface goes into the busy state. When the serial
interface is not selected, the interface sets the DTR signal MARK. When the printer is initialized or
returned to the idle state, the parallel interface goes into the ready state and the serial interface sets the
DTR signal SPACE. Caution that the interrupt signal such as the /INIT signal on the parallel interface is
not effective while that interface is not selected.

1.3.6 Printer language and Control Codes

Printer languages and control codes
1-20
:ESC/PC
:IBM X24E
:EPSON Remote
Rev. A