Data Bit 8; Data Polarity; Strobe Polarity; Response Polarity - IBM 6400 Setup Manual

Data Bit 8

The DATA BIT 8 parameter allows access to the extended ASCII character
set. This parameter is enabled by default. When this parameter is disabled,
the printer interprets bit 8 of each incoming data character as a zero,
regardless of its actual setting.
The extended ASCII character set is shown in the 6400 ASCII Programmer's
Reference Manual.

Data Polarity

The DATA POLARITY parameter must be set to match the data polarity of
your host computer.
STANDARD (the default) does not expect the host computer to invert
the data.
INVERTED expects the host computer to invert the data received on the
data lines. Ones become zeros, and vice-versa.

Strobe Polarity

The STROBE POLARITY must be set to match the data strobe polarity of
your host computer. When the host computer sends a data strobe signal to the
printer, this enables the printer to read the data bus.
STANDARD (the default) does not expect the data strobe signal to be
inverted.
INVERTED expects the host computer to invert the data strobe signal.

Response Polarity

The RESPONSE POLARITY parameter must be set to match the response
polarity of your host computer.
STANDARD (the default) does not invert the response signal.
INVERTED inverts the response signal sent to the host computer.

Busy on Strobe

BUSY ON STROBE determines when the Busy signal is asserted.
ENABLE (the default) asserts a busy signal after each character is
received.
DISABLE asserts a busy signal only when the print buffers are full.
4–48 6400 Line Matrix Printers Setup Guide, Cabinet and Pedestal Models