Raster Command Reference

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4. Printing Command Details

M Select compression mode

ASCII: M {n}

Hexadecimal: 4D {n}

Parameters

Definitions of {n}

No-compression mode (Enabled)

Reserved (Disabled)

TIFF (Enabled)

Description

⚫ Selects the compression mode. Data compression is available only for data in raster graphic transfer.

[TIFF(Pack Bits)]

⚫ 1-byte units

⚫ If the same data is repeated, the number of data units and that 1 byte of data are specified.

If different data is in a series, the number of data items and all of the different data are specified.

⚫ If the same data is repeated, the number of data units is specified as the actual number minus 1,

expressed as a negative number.

If different data is in a series, the number of data units is specified as the number of bytes minus 1,

expressed as a positive number.

⚫ If the above process results in more than 16 bytes (PT-H500/P700/E500) of compressed data, the data

is treated as being all different. As a result, the data will be 17 bytes (PT-H500/P700/E500) , including the

1 byte that specifies the data length.

Example

1 raster of raster graphics transfer:

Without compression:

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 22 22 23 BA BF A2 22 2B……

With compression:

ED 00 FF 22 05 23 BA BF A2 22 2B …

a b c

Since “00h” is repeated for 20 bytes, 20d -> 19d -> 13h changed into a negative number is EDh.

Therefore: ED 00

Since “22h” is repeated for 2 bytes, 2d -> 1d -> 1h changed into a negative number is FFh.

Therefore: FF 22

The following 6 bytes remain unchanged. 6d -> 5d -> 5h

Therefore: 05 23 BA BF A2 22 2B

Continue for the remaining number of bytes for the uncompressed data. Even if 00h continues until the

end, it cannot be omitted.