Data Block Transfer Order

The computer sends commands and parameters to the scanner in 8-bit code format. The scanner sends data to the computer in groups of 8-bit codes called ‘‘blocks.’’

Data block structure

Data blocks can take two forms: line data structure and block data structure.

Note:

The scanner must support the ESC d (Set line counter) command and be function level B4 or higher to transfer data using the block data structure.

A data block consists of two parts: the first part contains a header and status block; the second part is the scanned data extended.

Line data structure

Line data consists of a 4-byte information block followed by either an ID information data, an extended status data, or one line of the main scan image data.

The information block size is fixed at four bytes. The amount of data following differs depending on the data type. The byte counter in the information block specifies how much data is contained in the block.

2-26Command Usage