Dev_Tasks	
Not Available
#END#

SNP	
SNP-X protocol is a highly optimized extension of SNP. While it offers fewer functions than SNP, SNP-X is simpler to use and provides a significant performance improvement over SNP. It does not support PLC programming or configuration operations. SNP and SNP-X protocol allows for  following types of operation:1.Master- initiating device in a Master/Slave system(only available on CMM and PCM modules). 2. Slave-responding device in a Master/Slave system. SNP master and slave as implemented on  CMM module do not support PLC programming or configuration functions.LM90 may be connected to a CMM serial port configured as an SNP slave for data display and modification only. SNP and SNP-X protocols can be enabled on none, one, or both serial ports of  CMM module using either  RS-232 or RS-422/RS-485 electrical standard. Essentially, any combination of protocols, ports, and electrical standards are available with one exception: Series 90-30 CMM cannot support RS-232/RS-485 on port 1.Port selection, data rate, parity, flow control, number of stop bits, timeouts, and turnaround delay values can be configured.
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RTU	
RTU is a half-duplex protocol. It is commonly wired in either of two configurations: 2-Wire or 4-Wire.The RTU protocol as implemented on the CMMs and CPUs provides for Slave operation only. However, a MegaBasic application file is available that enables a PCM module to support the RTU Master or Slave implementation. 1.Master - the initiating device in a Master/Slave system. 2.Slave - the responding device in a Master/Slave system. The RTU protocol can be enabled on none, one, or both of the serial ports of the CMM module, on several CPU serial ports, and on PCM serial ports (using the MegaBasic application file) using either the RS-232 or RS-422/RS-485 electrical standard. Essentially, any combination of protocols, ports, and electrical standards are available with one exception: The Series 90-30 CMM cannot support RS-422/RS-485 on port 1. Port selection, station address, data rates, flow control, and parity values can be configured. 
#END#

Serial_IO	
Serial I/O protocol allows users to write a custom protocol for communicating with various serial devices such as bar code readers or pagers (not all CPUs support both Serial I/O modes). Serial I/O has two modes: Read and Write.
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CR_Task
TASK input at Commreq function block
#END#

Wait_Flag	
This flag determines whether  PLC will wait until the device serial ports receive the intended data before continuing. The request can either send a message and wait for a reply, or send a message and continue without waiting for a reply. If the Command Block specifies that the program will not wait for a reply, the Command Block contents are sent to the device and ladder program execution resumes immediately. This is referred to as NOWAIT mode. If the Command Block specifies that the program will wait for a reply, the Command Block contents are sent to the targeted device and the CPU waits for a reply for a maximum length of time specified in the Command Block. If the device does not respond in that time, ladder program execution resumes. This is referred to as WAIT mode.
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Idle_Tmout	
The idle timeout value is the maximum time the PLC waits for the device to acknowledge receipt of the request. For NOWAIT, this value is not used. (Any timeout value is ignored; it can be zero.) If WAIT is selected, this word specifies the idle timeout period, in 100-microsecond increments.
#END# 

Max_Comm_Tm	
This word contains the maximum amount of time the program should hold the window open when the device is busy. For NOWAIT, this value is not used. (Any timeout value is ignored; it can be zero.) If WAIT is selected, this word specifies the maximum time in 100 microsecond increments.
#END#

Protocol	
#END#

Port_Mode	
Master - the initiating device in a Master/Slave system. Slave - the responding device in a Master/Slave system. 
#END#

Data_Rate
In bits per second	
#END#

Parity	
The anticipated state, either odd or even, of a set of binary digits.
#END#

Flow_Control
The Flow Control field specifies the method of flow control to use at this serial port. Valid selections are NONE or HARDWARE. Note: The CMM modules do not support hardware flow control when used with an RS-485 interface. The NONE selection makes use of the signals Transmit Data (TD) and Receive Data (RD) only. The signal Request to Send (RTS), however, is used as a modem-keying signal. The RTS signal is energized for the Modem Turnaround Delay interval and during the character transmission; the RTS signal is then immediately de-energized. The HARDWARE selection makes use of the Transmit Data (TD), Receive Data (RD), Request to Send (RTS, Clear to Send (CTS), Data Carrier Detect (DCD), and Data Terminal Ready (DTR). 
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Turn_Delay	
The Turnaround Delay field specifies the duration of time required by the modem to turn the communication link around. The duration is specified in milliseconds and the default value is 0.
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TmOut	
Timeout. (CCM) The Timeout field displays the length of timeouts used for CCM on the target port. Timeout. (SNP) The Timeout field specifies a set of values for each of the SNP timers. 
#END#

BPC	
Bits Per Character
#END#

Stop_Bit	
Transmission of data in which time intervals between transmitted characters may be of unequal length. Asynchronous transmission is controlled by start and stop bits at the beginning and end of each character.
#END#

Interface	
The Interface field specifies the type of electrical interface used at this serial port. Valid selections are RS-485 or RS-232. Note that for the CMM311 module, port 1 operates as RS-232 only.
#END#

Duplex_Mode
The RTU protocol only supports half duplex operation; however, it may be wired in either a 2-wire or 4-wire arrangement. In 4-Wire RTU, the four wires are comprised of two transmit wires and two receive wires. In 2-Wire RTU, the transmit and receive pins are jumpered together in a parallel connection on the serial port connector at each device so that the two wires are shared by the transmit and receive functions. In the 2-Wire figures below, notice that SD (A) is jumpered to RD (A), and SD (B) is jumpered to RD (B).
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Device_ID
This is an identifier that distinguishes this device from others on the same network (for example: SNP ID, STA ADDR).
#END#

Dev_ID_RTU	
This is an identifier that distinguishes this device from others on the same network (for example: SNP ID, STA ADDR).
#END#
