Metrologic Instruments MS951 manual KB Parameter Inter Scan Code Delay AT and PS/2 Modes

Recall Defaults

D F 1

KB Parameter - Inter Scan Code Delay (AT and PS/2 Modes)

The time specified with an inter scan code delay bar code represents the amount of time between individual 9 bit scan codes. Each character of a bar code takes between two and twelve of these scan codes to be passed through to the PC via the keyboard interface. This parameter may need to be adjusted for operation with certain PC key- board BIOS’s. Network operating systems often use microprocessor time slices to ser- vice network information requests instead of the keyboard interface. While not an issue with manually entered key strokes, this timing can be critical with automatic scanner data entry. Inter-scancode delays can be a useful system tuning tool in these environments.

** 800 Microsecond Delay

O C 8

7.5 Millisecond Delay

O C 9

15 Millisecond Delay

O C 7

KB Parameter - XT - Clean-Up Bit

Some keyboard BIOS's require a "clean-up bit" to be transmitted prior to an actual scan code being clocked over to the motherboard. Enabling this feature will cause the scanner to send this extra bit to the host computer. More commonly found on older XT style BIOS's, and some AT BIOS's. (required by some NEC 80286 machines).

Enable Cleanup Bit

H H 1

** Disable Cleanup Bit

H H 2

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