Epson 420i SW1, SW1-7, No parity, Odd parity, Even parity, 3. ETXlACK Protocol, The following four baud rates are selected by DIP switches

3. ETXlACK Protocol

The printer sends an ACK (O6HEX) to the computer in response to the data block separated by ETX (03HEX) which was sent by the computer. If the communication buffer space goes below 4K bytes, ACK is not sent. If the buffer space is more than 4K bytes, ACK is sent through the TR line. The ACK’s output data format is the same structure as the input data.

Baud Rate

The following four baud rates are selected by DIP switches,

Data Length 7/8 Bit Selection

A 7 bit or 8 bit data length may be selected by DIP switch 1-3. When the switch is ON, the 7 bit length is selected. When the switch is OFF, the 8 bit length is selected.

Stop Bit

One bit or more are required for the stop bits. However, when DIP switch 1-3 is ON and is set to 7 bits, and when there is no parity setting by SW 1-6 and SW 1-7, there is a need for 2 or more stop bits.

Parity

Whether a parity bit is to be used, and whether odd or even parity is to be used is selected by SW 1-6 and SW 1-7. If a parity error is generated during the input of data, whether the data is ignored or a “*” is to be printed, is selected by SW 1-8. If ON, the data is ignored. If OFF, the “*” mark is printed.

	SW1 -6	SW1-7
No parity	OFF	OFF
	ON	ON
Odd parity	OFF	ON
Even parity	ON	OFF

Note: All DIP switch selections should be performed with the power OFF.

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