IBM 5150 PC Technical Reference (6025005, August, 1981) (PDF)

The ESC A code is the command only to store
spacing data into the memory. In other words,
even if spacing data was transferred into the
memory, the Printer does not actually carry out
the line spacing in accordance with the spacing
data. To execute the line spacing in accordance
with the stored data, the ESC 2 code should be
followed. Namely, the ESC 2 code is considered
as the execution command for the line spacing.
[DATA] AAAAAAA ICRI [LFl BBBBBBB ICRI !!£] IESC A+24 I
CCCCCCC ICR 1 I1I] DDDDDDD I ESC 21 ICR 1 [ill
[PRINT]
EEEEEEE ICRI ITIJ FFFFFFF ICRI ILFI
AAAAAAA}
BBBBBBB
CCCCCCC
DDDDDDD}
EEEEEEE
1/6 inch = 12 steps/72
1/3 inch = 24 steps/72
FFFFFFF
Note:
When "n" is actually transferred to the
Printer as data, it is transferred in the form
of a 7-bit binary number.
In case of "ESC A+24", actual output to
the Printer is performed as
HHH in hexadecimal
code.
2) ESC B+nl +n2+nk+NUL
(1«n>1O