6530 Programmer's Guide

Conversational Mode Operation
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6530 Programmer’s Guide
data is the data read from the device when a read operation is
specified. Only 255 bytes of text data can be returned at one time.
To perform sequential read operations, your application should
continue issuing the Esc } sequence until 0 bytes are returned in
data.
CR is a control character (0DH) that terminates the message.
See the appropriate programmer’s guide for your operating system for
more information about performing I/O operations on a device driver.
Load and Execute an Operating System Program (Esc - V)
The Esc - V sequence allows your application to start an MS-DOS
program (child process) from the 6530. The user must set the EXEC
function parameter to ON to allow this escape sequence. Refer to the
User’s manual for PCT/PC6530 for further information before disarming
this safety mechanism. The escape sequence has the following format:
Esc - V filename [parameters] CR
where:
filename is the file name of the operating system program to be
started. Only the file name (with the .exe or .com extension) should
be specified - not the path. This means the user must have the path
set correctly for the program file.
parameters specify the command line parameters (if any)
required by the program to be started.
This escape sequence is equivalent to the operating system execute
process function. Refer to the programmer's guide for your operating
system for more information.
Note When you execute this process, communications between the
host and the 6530 are discontinued until the process has
completed.