6530 Programmer's Guide

Overview
6530 Programmer’s Guide 1-15
System Reset A system reset clears all workstation or PC memory and reloads the
operating system. It is equivalent to cycling power off and on, except that
the power-on self test is not performed. After a system reset, the user
must restart the 6530. The user can invoke a system reset with the
Ctrl-Alt-Del keys.
Application
Programming
Interface
The way in which your application program interacts with the 6530
depends on the host operating system.
On a NonStop host, your application program interacts with the 6530
through procedure calls to the Tandem NonStop Kernel file system. These
procedure calls request various I/O operations, such as:
CONTROL – Executes device-dependent operations on an open
device. Used for forms control and modem connect/disconnect.
SETMODE – Sets or clears device-dependent functions for the
workstation or PC, such as switching to block or conversational
mode.
WRITE – Sends data to the 6530 (displayable data, control codes,
and escape sequences).
READ – Gets data from the 6530.
WRITEREAD – Sends data to the 6530 and waits for a response.
Useful for prompting the user for information in conversational
mode and for sending control codes and escape sequences that
initiate reads from the 6530, such as read cursor address.
These are generic procedure calls that can be used regardless of the actual
communications configuration. The file system accesses the appropriate I/
O process to handle the transfer of data over the communications line.
Chapter 4 provides more information on the Tandem NonStop Kernel
programming interface and gives an example application.