Publication 1766-RM001A-EN-P - October 2008
376 ASCII Instructions
ACB - Number of
Characters in Buffer
Instruction Type: output
Use the ACB instruction to determine the number of characters in the
buffer. On a false-to-true transition, the controller determines the total
number of characters and records it in the POS field of the control data
file. The channel configuration must be set to ASCII.
Entering Parameters
Enter the following parameters when programming this instruction:
• Channel is the number of the RS-232 port, Channel 0.
• Control is the control data file. See page 365.
• Characters are the number of characters in the buffer that the
controller finds (0…1024). This parameter is read-only.
• Error displays the hexadecimal error code that indicates why the ER
bit was set in the control data file. See page 390 for error
descriptions.
Addressing Modes and File Types can be used as shown below:
EN
DN
ER
ACB
Ascii Chars In Buffer
Channel 0
Control R6:1
Characters 2<
Error 0<
ACB
Execution Time for the ACB Instruction
Controller When Instruction Is:
True False
MicroLogix 1400 22.6154 µs 3.5250 µs
ACB Instruction Valid Addressing Modes and File Types
For definitions of the terms used in this table see Using the Instruction Descriptions on page 92.
Parameter
Data Files
(1)
Function Files
CS - Comms
IOS - I/O
DLS - Data Log
Address
Mode
Address Level
O
I
S
B
T, C, R
N
F
ST
L
MG, PD
RI/RIX
PLS
RTC
HSC
PTOX, PWMX
STI
EII
BHI
MMI
LCD
Immediate
Direct
Indirect
Bit
Word
Long Word
Element
Channel • •
Control •
• •
(1) The Control data file is the only valid file type for the Control Element.
efesotomasyon.com - Allen Bradley,Rockwell,plc,servo,drive
To Next Page
Loading...
Need help?
General
