Omega A2400 manual Command Descriptions, Closed Channel CC Extended

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Command Set 4-7

Command Descriptions

All the commands may be used with normal addressing or Extended Addressing unless otherwise noted. Commands that are exclusive to the Extended Address mode are noted near the right hand margin. For example:

Closed Channel (CC)

(Extended)

Closed Channel (CC)

(Extended)

The Close Channel (CC) command is an Extended Address Mode com- mand that is used to close the communications data channel in an A2400. A closed communications channel will prevent the flow of serial data present on the A2400’s RS-232 receive input onto RS-485 data lines. Assume Extended Address ‘01’ and the factory installed ‘{‘ and ‘}’prompts are used:

Command: {01CC

Response: *

Command: }01CC

Response: *01CC11

Digital Output (DO)

The DO command controls digital output (DO0/ARTS pin) on the module connector. The digital output allows the module to control an external circuit under host command. The DO command requires an argument of two hex characters.

The digital output is wired to the collector of a transistor in the module. The collector is connected to +5Vdc through a 5.6kΩ pull up resistor. If the digital output bit is set to ‘1’ the transistor is turned on and sinks current. Note that when the digital output bit is set to ‘1’ the electrical output is near 0 volts. If the digital output bit is set to ‘0’ the transistor is turned off and sinks no current. See Figure 2.1 for details.

Assume that you wish to turn the digital output bit on (sinking current). Set data bit 0 to ‘1’. Since the module has only one digital output, all the other bits are ‘don’t cares’. For example, this command will turn the output ‘on’:

Command: $1DO01

Response: *

Command: #1DO01

Response: *1DO014F

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Contents User’sGuide For immediate technical or application assistance Servicing North AmericaServicing Europe Revised 4/17/95 Omega Engineering ONE Omega DriveBOX STAMFORD, CT Phone 1-800-DAS-IEEETable of Contents Chapter Getting Started IntroductionSystem Overview Leased Lines$1RD +99999.99Default Mode Page Block Diagram Chapter Functional DescriptionFunctional Description Pinout A2400 Operation RS-485 TerminationCharacter Filter Page Programmable Delay Times Page Command $1RD Response *+99999.99 Chapter CommunicationsDO, OC, CC, RD, REA, RID, RLP, RS, RSP, RSU Communication RS-485 Multidrop System DATA+Page Chapter A2400 Command Set Command StructureData Structure Write ProtectionMiscellaneous Protocol Notes Response StructureCommand Checksum Long Form Responses?1 BAD Checksum ?1 Syntax Error$1WEF A2400 User Commands A2400 Command Set RT3Command Descriptions Command 01CC Response Response *01CC11 Digital Output doCommand $1DO01 Response Command #1DO01 Response *1DO014F Closed Channel CC ExtendedCommand $1DO00 Response Command #1DO00 Response *1DO004E Extended Address EA#1ID Tank Farm $1ID Tank Farm1ID Tank Farm 1CD Open Channel OC Extended Command 01OC Response Response *01OCEDRead Data RD $1RID Tank Farm#1RID 1RID Tank Farm 11F$1RSU #1RSU$1RSP #1RSPResponse *1RT1+00100.00DC Read Time Delay 2 RT2 Read Time Delay 1 RT1Response *+00100.00 Page Page Short Prompt SP Command 01WE Response *01WE27 Error MessagesAddress Error BAD ChecksumCommand Error Parity ErrorSyntax Error Value ErrorCommand Syntax Chapter Setup Information/SetUp Command$1SUbyte 1byte 2byte 3byte Byte Byte 1 Ascii Printable Characters HEX AsciiParity Baud RateCommand $1WE Response Command $1SU31020000 Command $1RS Response *31070000Command $1RS Response *31020102 Command $1WE Command $1RR Response BitByte 2 Linefeed, Parity and Baud Rate BaudNormal addressing Chapter Delay Time Programming Delay Time Programming Page Command $1T3+00050.00 Set T3 to 50 ms Response Command $1RT1 Response *+00100.00Chapter Power Supply Symptom RS-232 Module is not responding to commands Chapter TroubleshootingSymptom RS-485 Module is not responding to commands Open/Close Channel Commands Command 01WE ResponseChapter Extended Addressing Typical system overview Command 01OC Response Command $1RD Response +00100.00 Typical $2RD +00123.45Command 01CC Response Command 02OC ResponseStructured Addressing Extended Address SyntaxOC and CC Command Formats Implied CC CommandImplied OC Command Command ResponseCommand 01$1RD Response *+00100.00 Command Response *01OC1D Single Command Module AddressExplicit Open and Close Channel Commands Command 01CC Response 01CC11 ‘11’ is the checksum Command 02OC Response 02OC1E ‘1E’ is the checksumChapter Transparent Mode Transparent Mode FunctionsA2400 interfacing a PLC to a leased-line modem A2400 networking several RS-232 devices to a host computer A2400 interfacing a laboratory instrument with modules Transparent Mode Adding secondary control using A2400 modules Transparent Mode WARRANTY/DISCLAIMER Shop online at omega.com