ProSoft Technology MVI71-GSC - Manual (Page 47)

Reference MVI71-GSC ♦ PLC Platform
Generic Serial Communication Module
ProSoft Technology, Inc. Page 47 of 82
January 31, 2008
1.15 Functional Overview
This section provides an overview of how the MVI71-GSC module transfers data
using the protocol. You should understand the important concepts in this chapter
before you begin installing and configuring the module.
5.1.5 General Concepts
The following discussion explains several concepts that are important for
understanding the operation of the MVI71-GSC module.
Module Power Up
On power up the module begins performing the following logical functions:
1
Initialize hardware components
2 Initialize PLC backplane driver (BTR/BTW or side-connect)
o
Test and Clear all RAM
o
Initialize the serial communication ports
o
Wait for Module Configuration from PLC processor
o
Initialize Communication ports
3
Set up the serial communication interface driver on the selected ports
4 After the module has received the Module Configuration Block from the
processor and the module is configured, the module will begin receiving and
transmitting messages with devices on the serial ports.
Main Logic Loop
Upon completing the power up configuration process, the module enters an
infinite loop that performs the following functions:
Call I/O Handler
Call CFG/DEBUG Port
Driver
Call Network Server
Drivers
Call I/O Handler
Transfers data between the module and processor
(user, status, etc.)
Call Serial Port Driver
Rx and Tx buffer routines are interrupt driven. Call to
serial port routines check to see if there is any data
in the buffer, and depending on the value, will either
service the buffer or wait for more characters.
Call Serial Port Driver
(Configuration/Debug Port)
Rx and Tx buffer routines are interrupt driven. Call to
Cfg/Dbg port routines check to see if there is any
data in the buffer, and depending on the value, will
either service the buffer or immediately return.
From Power Up Logic