Matrix Orbital GLK24064-25 Legacy - Manual (Page 30)

GLK24064-25 rev. 06 30
Based on the table, the byte 01001011 can be represented in hex as 4B, which is usually written as any of
4Bh, 4BH, 4B hex or 0x4B.
The numbers can also be expressed in decimal form if preferred.
8.3.1 ASCII Characters
Since computers deal internally with numbers only, but externally with both letters and numbers, several
schemes were developed to "map" written characters to numeric values. One such scheme has become
universal, the American Standard Code for Information Interchange, or ASCII. ASCII tables are readily
available from a number of sources. A few examples will do here:
The letter A has a value of 65 decimal or 41 hex
The letter a has a value of 97 decimal or 61 hex
The number 0 has a value of 48 decimal or 30 hex
The number 9 has a value of 57 decimal or 39 hex
This gives rise to the possibility of confusion when parameters are being set on the GLK24064-25. For
example, some commands use a [type] parameter to indicate a file type. We're told that acceptable values
are 0 and 5. All parameters must use numeric values (i.e. the actual byte values). If we send the ASCII
number 0 by mistake it will actually give the value 48 decimal (30 hex) to the parameter, which is wrong.
In the tables given in the following sections ASCII characters are shown as 'A', with single quotes.
8.4 Text Commands
See Chapter 3 for command descriptions. Syntax in the tables below is given in hex, decimal and decimal
with ASCII, in that order, one per line.
Table 8-1 Text Commands
Command Syntax Default Notes
Auto line wrap on FE 43
254 67
254 'C' on Enables line wrapping (not word wrap).
Auto line wrap off FE 44
254 68
254 'D' on Disables line wrapping.
Auto scroll on FE 51
254 81
254 'Q' off Enables scroll at bottom of screen. Text will
push display up one line to make room for new
line.
Auto scroll off FE 52
254 82
254 'R' off Disables auto scroll. Text will wrap to top left
and overwrite existing text.
Set text insertion
point FE 47 [col] [row]
254 71 [col] [row]
254 'G' [col] [row] n/a Sets text insertion point using the base size of
the current font
Set text insertion
point to top left FE 48
254 72
254 'H' This command moves the text insertion point to
the top left of the display area, based on the
metrics of the current font. See "Set font
metrics" (section 3.3.7) for more details.