Introduction: The Engineering Value of PCS Series Operation Console
The Lauer PCS series is a programmable control console that includes four models: PCS 009, PCS 090, PCS 095, and PCS 095.1, each offering display and button configurations of different sizes. The core design concept of this series of devices is "the same hardware, endless changes" - through a set of hardware with different parameter configurations, it can cope with thousands of operating scenarios without complex I/O wiring and extensive wiring.
Main differences among different models:
PCS 009: 4-line x 20 character LCD, 8 function keys (with green LED), 10 key numeric keypad, suitable for compact operation requirements
PCS 090: 2-line x 40 character LCD, 8 function keys (with green/yellow dual color LED), suitable for simple text display scenarios
PCS 095/095.1: 4-line x 40 character LCD, 16 function keys (with green/yellow dual color LED), PCS 095.1 additionally supports printer interface and 4 data recording switches
All models support RS232/TTY, RS422/RS485 serial communication, with a front panel protection level of IP65, operating temperature of 0-50 ℃, and storage temperature of -25~70 ℃. The configuration software PCSPRO runs in the MS-DOS/DR-DOS environment and downloads project data to the device Flash EEPROM through programming cable PCS 733. This article is based on the official technical manual and systematically outlines its core functions such as communication principles, variable formats, menu configuration, and priority management, helping engineers quickly master this classic HMI tool.
Communication principles and data area structure
2.1 Communication Model
The communication between PCS and PLC adopts the "shared data area" model, which supports a maximum of 256 words (W0~W255, 16 bits per word). The communication direction is bidirectional:
PCS → PLC: Write button status, preset values, PCS status information
PLC → PCS: Write LED control, command words, message bits, variable values
Two principles of data exchange:
Expander driver: Running expander program in PLC to process PCS data packets, suitable for systems that support indirect addressing
Direct drive (such as AS511. DRV): directly reads and writes PLC fixed data area, suitable for systems that do not support indirect addressing or scan cycle sensitivity
2.2 Data Area Allocation (Standard Driver)
Regional character range direction function
System area W0~W3- used internally by the driver, W3 is a communication error word
Functional area W4~W14 PCS → PLC press key positions (W4~W5), PCS status (W6~W9), LED status (W10~W11), command words (W13~W14)
Message area W15~W22 PLC → PCS 128 message bits (corresponding to message text 0~127)
Expansion area W23~W29 mixed PCS 095/095.1 for F9~F16 buttons (W23) and additional LEDs (W24~W25)
Variable area W30~W255 mixed external variables (actual value/preset value)
Detailed explanation of variable system
3.1 Variable classification
PCS supports 650 external variables (user-defined) and 6 internal variables (predefined). Variables are divided into three categories:
ACTUAL (actual value): displayed only and cannot be modified
NOMINAL (preset value): can be displayed and modified
NOMINAL-P (protected preset value): can only be modified when W14 position 7=1, usually controlled by key switch or DIL switch
3.2 Detailed Explanation of Variable Format
BIT variable: Maps two strings to a 0/1 state of a certain bit. Immediately write the modifications to the PLC. For example, the "CLOSED/OPEN" status display.
STRING variable: maps 256 values of a byte to 256 strings. After modification, press ENTER to confirm writing. Suitable for multi state selection (such as "Service/Setting UP/AUTOMATIC").
CSTRING variable: Similar to STRING, but immediately written to PLC after modification without pressing ENTER.
BCD variables (BCD-1/2, BCD0-1/2): Display BCD encoded values in PLC as decimal numbers. BCD-1 is 4 bits (1 word), BCD-2 is 8 bits (2 words). BCD0 variant displays leading zeros.
BIN/VBIN variables: Convert binary values in PLC to decimal display. BIN is unsigned, VBIN is signed (±). Supports scaling, decimal point, and leading zero control. Subtype-1 (16 bits) and -2 (32 bits) are calculator style inputs; -A and - B are shifted inputs (from right to left).
WORD variable: Display 16 bit words in binary (KM), hexadecimal (KH), or double decimal (KY) format. It can be modified one by one in the menu.
ASCII variable: A string of up to 16 characters (8 characters) that supports any ASCII code input.
TIMER variable: 3-digit BCD time value+time base (0-3), suitable for timer setting.
Menu system and variable editing
4.1 Menu Structure
PCS supports up to 127 menus, with a maximum of 255 nodes per menu. Each node corresponds to an operation text (0~127), which can contain up to 4 variables (PCS 009/095) or 8 variables (PCS 090). The PLC starts the menu by writing the menu number (1-127) through W14 bits 0-6, and ends the menu by writing 0.
Menu navigation:
The first defined node is the Start Node
Arrow keys navigate between nodes, with arrow key LEDs indicating available navigation directions