Metrologic Instruments MS951 manual RS-232 Parameter Parity, RS-232 Parameter Data Bits

Enter/Exit Program Mode

* *

RS-232 Parameter - Parity

Parity is an additional digit that makes the number of bits in the ASCII code odd or even. The scanner’s parity must match the host’s parity.

**Space Parity Select this option to make the parity bit always 0.

P

A

1

Even Parity

Select this option to make the additional parity bit either a

0 or 1 to guarantee an even number of bits.

3

P

A

Mark Parity

Select this option to make the parity bit always 1.

2

P

A

Odd Parity

Select this option to make the additional parity bit either a

0 or 1 to guarantee an odd number of bits.

4

P

A

RS-232 Parameter - Data Bits

RS-232 serial communication requires ASCII data to be transmitted in either 7 or 8 data bits. In addition, one parity bit will be transmitted. If necessary, scan the appropriate bar code that matches your host device’s requirements.

Generally, if 7 data bits are selected, 2 stop bits are transmitted. If 8 data bits are selected, 1 stop bit is transmitted . Stop bits are actually just an idle trans- mit line. From the scanners perspective, they are only important if the scanner is receiving more than 1 byte of information at a time. For most applications, the scanner is a transmit only device.

8 Data Bits

D 8 1

** 7 Data Bits

D 8 2

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