User`s manual

BD2-2860 User’s Manual
CITIZEN
21
7.3 Date configuration
(1) Start bit
(2) Data bit (+ Parity bit)
(3) Stop bit ( 1 or more )
(1) Start Bit
In 1/2 bit from the mark-to-space starting edge, state is read once again. When "space" state is confirmed, it
is recognized as the start bit. If it is "mark" state, it is not taken as the start bit.
Without taking it as an error, detection of a start bit is carried out onceagain.
(2) Data Bit + Parity Bit
Data bit and parity bit are sampled at 1/2 start bit for time length equal to 1 bit. The state thus sampled is
taken as the data for the bit concerned. Bits are named as Bit 0, Bit 1.…. Parity bit counted from the one
close to the start bit.
(3) Stop Bit
The stop bit is a mark level of 1 bit or more. With "space" having been detected on detection of a stop bit,
framing error takes place.
Mark
b1,b2,b3 ····
(1) (2) (3)Space