Status byte
This byte indicates the color of the image data or the state of the scanner. Each bit in the Status byte has a different meaning, as shown in the following diagram. Currently, bits 0, 1, and 6 are reserved (not used).
Error flag (bit 7)
This flag is set to ‘‘1’’ when an error other than a command error occurs. In this case, no data follows, so the byte counter is set to 0 (00H, 00H).
If a system error occurs, the scanner accepts only the ESC F and ESC f commands. These two commands are used to determine if a system error has occurred.
Area end flag (bit 5)
This flag is set to ‘‘1’’ when the data block is the final block of scanned data in the scanning area. Do not send an ACK code to the scanner after receiving the final data block (when this flag is set to 1).
Option flag (bit 4)
This flag is set to ‘‘1’’ when an option is installed.