IBM 5150 Hardware Reference Manual page 102

3) ESC 2 (Escape 2)
Receipt of an "ESC" followed by ASCII code
"2" causes the line spacing to be set at 1/6 inch.
When the POWER switch is turned on, the line
spacing is set at initia11/6 inch. The ESC 2 code is
also a command to execute "ESC A+n" modes
(described later).
4) ESC 8 (Escape 8)
The ESC 8 code makes it possible to transmit data
even if there is no paper in the Printer. This code
should be transmitted before the Printer runs out
of paper. After transmitting this code, when the
Printer runs out of paper, the PE signal of the
interface connector turns to High level; the
ERROR signal remains at High level.
5) ESC 9 (Escape 9)
This code cancels the ESC 8 condition. When the
power is turned on, the Printer is initialized into
ESC 9 status. Therefore, the Printer cannot
receive data when there is no paper.
6) ESC SI
This code functions the same as "SI".
7) ESC SO
This code functions the same as "SO".
(b) ESC alphabetic control
Receipt of an "ESC" code followed by ASCII code
"X"(alphabetic code) permits each of the following
functions to be performed.
Note: "n" represents a 7-bit binary number, and the
most significant bit is not treated as data. "+" is
inserted for the purpose of legibility only, and
should not be input in actual operation.
1) ESC A+n
This code specifies the amount of line spacing in
the Line Feed 1 «n> 10<85 (Decimal): "n" is a
binary number. "n"= 1 is equivalent to 1/72 inch
paper advancement. Since the distance between
any two dot wires of the print head is 1/72 inch,
any line spacing in increments proportional to the
distance between the dot wires can be established.
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