Microcom 334M Operator's Manual page 134

Chapter 6
printer. Please note that the compressed format is only usable on 8-bit data connections
and will NOT function on 7-bit data connections.
6.4.1 Uncompressed Graphic Downloads
The uncompressed converted GRAHIC file can be sent on either 7 or 8-bit connections, is
more flexible, and encodes using ASCII-HEX, but this method results in a much larger file
size than a compressed format.
The converted GRAPHIC file can be sent to the printer via any active printer port. A
terminal emulation program such as Hyper Terminal, ProComm, Tera Term, etc is
commonly used.
Note: It is highly recommended to use hardware flow control.
6.4.2 Compressed Binary GRAPHIC Downloads
The compressed format shortens the download time by reducing the number of bytes sent
to the printer. Data compression is accomplished by converting strings of 0 HEX or FF HEX
to shorter byte-plus-count sequences. These sequences are then expanded to the original
number of bytes inside the printer. A compressed binary converted GRAPHIC file must be
sent on a 8-bit data connection.
The printer must be setup to accept downloaded binary compressed files by setting
Software Switch #3, position 7 to "1". Otherwise, the file may be sent to the printer through
any active printer port.
6.5 Advanced GRAPHIC Format Conversion for Programmers
The following sections are provided to developers who wish to create usable GRAPHIC
images within their own applications. Commands in the following section are not typically
seen for users using Microcom GRAPHIC utilities.
6.5.1 Save Compressed Graphics to RAM (D107)
The following is the format of the ^D107 command when used to store a compressed
GRAPHIC image file into RAM.
^A<RAM Memory Slot Number>^D107<CR>
<Rotation> <Count> <Image Data>
Where:
<RAM Memory Slot Number> is the memory slot location (1-255) where the GRAPHIC will
be saved in the printer's RAM memory. The printer uses the same TCI of "8" to select
downloadable fonts or graphics. Therefore a font and a graphic cannot have the same Slot
Number or CGN number.
<Rotation> is an 8-bit integer, 0 for an upright GRAPHIC and 1 for a GRAPHIC rotated 90-
degrees counter-clockwise.
<Count> is a 32-bit integer, least significant byte first. This is the number of uncompressed
bytes that the GRAPHIC image uses, not the number of bytes that will actually be
334M Operator's Manual - 880060-0110
Downloadable Graphics
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