Chapter 3 Communications Operations of the BHT
Transmission Code and Bit Order
All characters should be coded to 7 or 8-bit code for data transmission. The transmission bit order is LSB
(Least significant bit) first.
What follows is an example for transmitting character A (41h, 01000001b) with an even parity and a
single bit each for start and stop bits.
Vertical Parity
A vertical parity bit is a redundancy bit which is added to every character to be transmitted in order to
check that data has been transmitted accurately. The parity bit should be set to "1" or "0" depending
upon the parity parameter setting, to make the number of set bits in the character even or odd. The
receiver counts the number of set bits in the transmitted character code to make sure that it has the
selected number (even or odd) of set bits.
The vertical parity bit is positioned immediately following the MSB (Most significant bit) as shown below.
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