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4 data composition – Citizen Systems iDP-3535 User Manual

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iDP-3535 User’s Manual

CITIZEN

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5-4 Data Composition

1 Start bit
2 Data bits (and parity bit)
3 Stop bit (1 bit more)

1) Start bit

1/2 bit past the line dropping from MARK to SPACE, a status reading is taken again. If the reading is SPACE,
a start bit is recognized.

2) Data bits and Parity bit

Data bit and Parity bit are checked out every bit form the half point of start bit.
Signal level of these points (Mark = 1, Space = 0) are read as input data.
The sequence of these bit is Bit 0, Bit 1 ~ Parity bit from Start bit.

3) Stop bit

The stop bit consists of one or more bits at “mark” level. When “space” level is detected for a stop bit,
a framing error occurs.