X25AM Programming Manual

ITI Applications
X25AM Programming Manual—527201-001
2-20
ITI Application Programming
The translation of PARITY is shown in the following table. The most significant bit
(leftmost bit) of each data character is the parity bit.
PAD parity generation for outgoing data and parity checking for incoming data is set
with PAD parameter 21.
ITI Application Programming
ITI application programming is divided into three subsections. The first section is
organized by task to help you understand what needs to be coded in your application.
The second section is organized in alphabetical order by procedure. This provides you
with a more convenient method for referring to the procedures. The third section
contains a program example.
ITI Programming Tasks
Programming your application involves coding some or all of the following tasks:
opening a subdevice file, setting options, reinitializing values; retrieving information,
waiting for incoming calls, and posting calls.
Opening a subdevice file
A subdevice must be opened before any other file access can take place. When the
OPEN procedure completes, a file number is returned to your application. The file
number identifies the subdevice file in subsequent file-system calls. The OPEN flags
are always assumed to be READ/WRITE regardless of how they are coded.
PARITY Description
PARITY EVEN Set the parity bit to 1 or 0 to make the number of 1s
even.
PARITY ODD Set the parity bit to 1 or 0 to make the number of 1s odd.
STRIP PARITY Make the parity bit equal to 0.
Table 2-7. X.3 Parameter 21 Values
Value Parity Generation Parity Checking
0No No
1No Yes
2Yes No
3Yes Yes