Toshiba S20LP instruction manual Message transmission, Computer link protocol, PC link protocol

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6 F 3 B 0 3 5 6

7. Message transmission

7.1 Message transmission

The message transmission is text transmission to be performed communication on request. This transmission is following two protocol.

∙Computer link protocol

∙PC link protocol

7.2Computer link protocol

The host machine can communicate to a T2N/T3H on the S20LP using the computer link protocol. Since this function executes the station and firmware, there is no need to create pecial user programs for the T2N/T3H using the slave station.

The host machine used this protocol can execute following process for the T2N/T3H.

∙Upload or download user programs.

∙Status observation (reading out RUN/HALT/ERROR status).

∙Read or write register/device data.

∙Execute control commands.

The computer link protocol cannot execute following process.

∙T2N/T3H is Down mode.

∙A S20LP-station except for ONLINE and STANDBY mode.

7.3PC link protocol

This section presents an overview of the SEND and RECV instructions, which are the instructions that are used to control the S20LP-station from T2N/T3H user programs. S20LP- station transmission control (PC link protocol transmission) is performed solely using the SEND and RECV instructions. See the individual items for details on the actual requests sent to the S20LP.

The PC link protocol allows one T2N/T3H on network to write or read register data to another T2N/T3H.

When this function is used on the PC link slave station, there is no need to create special user programs for the T2N/T3H using the slave station.

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Contents T2N/T3H stations Important Information Preface Contents Introduction to S20LP System configurationT2N include of S20LP Port Station hardware∙ Overview SN325 SN325For SN325 ∙ Status LEDsS20LP port for T2N PU245N ∙ Loader port ∙ Station number setting switches∙ Transmission cable connectors ∙ Reset switch only SN325Menu LS overview⎯ 10 ⎯ S20LP-station specifications SpecificationsS20LP system specifications Scan transmission overview Allocation and network assignment by T-PDS Setting the data send block by S-LSSettings on T-PDS Setting for data linkageStation number setting Link PDS screen example Block Send Receive ⎯ 18 ⎯ Global ⎯ 20 ⎯ Settings on S-LS ⎯ 22 ⎯ ⎯ 23 ⎯ ⎯ 24 ⎯ ∙ Message Transmission ∙ Scan Access∙ Start with Standby mode ∙ Scan Transmission∙ Target Scan Time Data linkage example ∙ Settings on T-PDS Setting on S-LS LS setting screen 2 for STN #2 Cable connections ∙ Transmission cable breakage RAS functionBehavior in trouble ∙ Station downDuring operation Self-diagnostic functionAt initialization at power on T2N LED indicationSN325 RAS information monitored in T2N/T3H Online map Station statusLoop map Only T2N Standby mapNumber 1-64 on the screen shows the Station number RAS information monitored on S-LSSelf Station Station No.01 Offline Select the Station Number Click the Status Display Station down information Possible error message are as followsFunction Instruction SpecificationExpanded data transfer instruction Instruction format Transfer parameter table Parameter and construction∙ Operation Sample programRemarks PC link protocol Message transmissionMessage transmission Computer link protocol∙ Send CMD Transfer parameters aStatus B TermSTS Status Meaning Detailed Information Send completion status Transfer parameters PC link protocol transmission Data writeRID Important items Status See 7.3 5 for details on bits C, D, E, and FXW/YW PC link protocol transmission Data read ⎯ 57 ⎯ SW067 Write enabled Remarks PC link protocol transmission programLength END Scan cycle Appendix⎯ 63 ⎯ PDS remote programming PDS Setup options screen