IBM 32x, W2H, 31x manual Format of the Horizontal Scroll Start command is as follows

11-9-2005 Input/output device commands

The format of the Horizontal Scroll Release command is as follows:

1B 5C 3F 4C 4D 45

Purpose:

This command resets horizontal scroll mode.

The format of the Horizontal Scroll Display Mode Set command is as follows:

1B 5C 3F 4C 4D Pm 3B Pl 3B Pt 3B Pn 3B Pd...Pd

Purpose:

This command sets horizontal scrolling options. The control bytes embedded in the command sequence (represented by Pm, Pl, Pt, and Pn in the preceding command format), change the scrolling characteristics. Pd...Pd represent the data bytes. This command does not affect previous display settings.

Pm (screen		6	(X'36'):		5x7 dots,		4	rows
mode)		7	(X'37'):		5x7 dots,		5	rows
		8	(X'38'):		16x16 dots,			8x16 dots, 2 rows
Pl	(row)	1	∼ 4	(X'31'∼X'34'): Pm=6
		1	∼ 5	(X'31'∼X'35'): Pm=7
		1	∼ 2	(X'31'∼X'32'): Pm=8
Pt	(scroll	1	(X'31'):		1	digit/10	ms
speed)		1	(X'32'):		1	digit/20	ms
Pn (number		The number of data bytes (1 for half size letter, 2 for full size letter,
of	characters)	maximum is 128 (X'80').
Pd...Pd		This represents the data characters.

The format of the Horizontal Scroll Start command is as follows:

1B 5C 3F 4C 4D 47

Purpose:

This command begins horizontal scrolling on all lines. All subsequent commands are ignored until a Scroll Mode Release command is sent.

The rules of operation for the Horizontal Scroll On All Lines are as follows:

vAny codes not described here are ignored.

vThe most recent Display Mode Set command becomes effective in one screen scroll setting before the Scroll Start command is performed.

vA screen scrolls from right to left, dot by dot.

vThe range of the display that is being scrolled is defined by the screen mode setting.

vThe command is canceled when Pn = X'00'. After it is canceled, displayed characters are cleared, and the write-in position moves to the most significant digit of the row.

vThe command can be started only on a single line.

vA character’s Display Mode Set command (reverse, blinking, and so on) can be added with the display data frame. If the command is written twice or more in one scroll data frame, only the first command is valid; others are ignored.

Appendix A. Input/output device commands A-15