11-9
IM CW120-E
Communication Functions
11
11.3 Data Format
The serial interface of the CW120/121 performs asynchronous transmission.
In an asynchronous transmission, each character is carried in such a way that
7 or 8 data bits are preceded by a start bit and followed by a parity bit
(optional), and 1 or 2 stop bits in order (see also the figure below).
Data bits
(7 or 8 bits)
1 character
Stop bit
(s)
1
1 or 2
2
Parity bit: Odd,
even, or none
Start bit
Idle state of line
Puts the line back
to idle state
(dashed line)
or sends start bit
(solid line).