Data Stream - IBM 3164 ASCII Manual

Chapter 5. Programming considerations
Data stream
To and from the host
5-2
This section defines the data stream used by the IBM 3164 to communicate
with the host system. The IBM 3164 data stream consists of data characters
and control characters. Oata characters are the ASCII codes from X'21 ' to
X'7 E' and are used to represent messages or text. Control characters are the
codes from X'OO' to X'20 1 and X'7F'. (Refer to the ASCII Line Code Table
on page 5-79.) The control characters may be used alone or with other
control or data characters to perform multiple functions; such as in the OLE
sequence (OLE.EOT, OLE.STX, OLE.ETX, OLE.OC2, or OLE.OC4) or in the
ESC sequence as commands/responses.
Each character consists of 7 - or 8- bit codes depending on which Word
Length Option you selected.
¢
I
bit 1
I
bit
21
bit
31
bit
41
bit
51
bit
61
bit
71
¢
I
bit 1
I
bit
21
bit
31
bit
41
bit
51
bit
61
bit
71
bit
81
Each character has a parity bit at the end whose characteristics (000, EVEN,
SPACE, MARK, or None) are selected by the Parity option. If you choose the
None option, the character will not have a parity bit.
¢
I
bit i \ bit 2\ bit 3\ bit
41
bit 5\ bit 6\ bit
71
Parity
I
In addition to the parity bit, the data has one start bit and one or two stop bits
which can be selected as an option.
The IBM 3164 samples the data bits until the stop bit (or bits) is received.
(