Omega A2400 manual

Page 36

Command Set 4-15

T2 is specified in units of milliseconds with a range of 0 to 2000ms. The time data must be formatted as a plus sign, five decimal digits, a decimal point, and two additional digits:

Command:

$1T2+00350.00 (Set T2 to 350 ms.)

Response:

*

Command:

#1T2+00350.00 (Set T2 to 350 ms.)

Response:

*1T2+00350.0092

Set Time Delay 3 (T3)

T3 is the delay time between the last character transmitted to the host and the trailing edge of RTS signal which turns off the remote transmitter. The A2400 will transmit data to the modem until the receive buffer is empty. When the receive buffer is empty, and the last character has been transmit- ted, time delay T3 is activated. T3 provides two functions: it provides a clean break between the transmitted data and the turn-off of the radio transmitter, and it allows the host to poll more data without keying the transmitter on and off. During time T3, the host may transmit another command which would pass through the A2400 to the RS-485 bus. Typically, this command would generate a response from a device on the RS-485 bus. If the response data is received by the A2400 before T3 is complete, T3 is canceled and the received data is immediately transferred to the modem. When the receive buffer is empty, T3 is activated again, and the cycle repeats itself. This allows the host to establish communications with the remote radio and talk back and forth without wasting time re-keying the transmitter for each response.

If T3 times out and the receive buffer is empty, the radio connection is terminated by turning off the RTS signal.

Command:

$1T3+00050.00

(Set T3 to 50 ms)

Response:

*

 

Command:

#1T3+00050.00

(Set T3 to 50 ms)

Response:

*1T3+00050.0090

 

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Contents User’sGuide Servicing North America For immediate technical or application assistanceServicing 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 RS-485 Termination A2400 OperationCharacter 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 Syntax Error ?1 BAD Checksum$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 Command 01OC Response Response *01OCED Open Channel OC ExtendedRead Data RD $1RID Tank Farm#1RID 1RID Tank Farm 11F$1RSU #1RSU$1RSP #1RSPRead Time Delay 1 RT1 Response *1RT1+00100.00DC Read Time Delay 2 RT2Response *+00100.00 Page Page Short Prompt SP Command 01WE Response *01WE27 Error MessagesAddress Error BAD ChecksumCommand Error Parity ErrorSyntax Error Value ErrorChapter Setup Information/SetUp Command Command Syntax$1SUbyte 1byte 2byte 3byte Byte Byte 1 Ascii Printable Characters HEX AsciiParity Baud RateCommand $1RS Response *31070000 Command $1WE Response Command $1SU31020000Command $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 Chapter Troubleshooting Symptom RS-232 Module is not responding to commandsSymptom RS-485 Module is not responding to commands Command 01WE Response Open/Close Channel CommandsChapter 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 Response *01OC1D Single Command Module Address Command 01$1RD Response *+00100.00Explicit 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