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Table of Contents Brief description of the MOBY file handler ASM 421 hardware Programming the MOBY I ASM 421 module Cold start and restart ASM 421 Interface Module Checking entry and exit of MDS in SLG transmission window System and transmission times Technical Description Troubleshooting and error messages...
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This product can only function correctly and savely if it is transported, stored, set up, and installed correctly, and operated and maintained as recommended. Trademarks SIMATICR and MOBYR are registered trademarks of SIEMENS AG. Disclaimer of Liability Copyright Siemens AG 1995, 2002 All rights reserved...
6GT2 097-3AH00-0DA2 ASM 421 Technical Description Brief description of the MOBY file handler The ASM 421 is a serial interface module for the MOBY I identification system. It can be driven from any computer, PC or PLC using the 3964R procedure. The MOBY I file handler is implemented on the ASM 421.
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ASM 421 Technical Description 6GT2 097-3AH00-0DA2 Similarities between MOBY file handler and a floppy disk – The user does not access physical memory addresses – The user addresses the data via logical names, which consist of up to eight letters –...
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6GT2 097-3AH00-0DA2 ASM 421 Technical Description Formats of different MDS memories: MDS units with various memory sizes are available with MOBY I. Each type of MDS must be formatted before processing with the file handler. During formatting, the MDS is given a data structure, divided into system area, directory and user data.
ASM 421 Technical Description 6GT2 097-3AH00-0DA2 ASM 421 hardware Backplane connector (X1) Fuse (T 315 mA) EPROM Switch bank (S1) for setting mode of operation Active Error 3 LEDs: LED: indicates a fault (see table in chap. 7) yellow LED: indicates that the SLG device is active green LED: indicates that an MDS is present 9–way subminiature D connector (screw locking) (X2) for connecting the SLG read/write device...
6GT2 097-3AH00-0DA2 ASM 421 Technical Description Technical data Environmental conditions: 0 °C to + 55 °C – operating temperature: – 40 °C to + 70 °C – storage temperature: Degree of protection to IEC 529: IP 00 Serial interface (to computer/PC): –...
ASM 421 Technical Description 6GT2 097-3AH00-0DA2 Pin assignments 2.2.1 Pin-outs of X1 backplane connector Power supply Serial interface to user Optional control and signal line Optional SLG connection Protective ground (shield) 24 V Interface (type dependent) Interface (type dependent) V.24 RS422 V.24 RS422...
6GT2 097-3AH00-0DA2 ASM 421 Technical Description 2.2.2 ASM 421 connector system Connector: The connector used with the ASM 520 is a 48-way male connector conforming to DIN 41612 design F, whose soldering pins are bent through 90°. Rows z and b only are connected and soldered directly to the ASM 520.
10 Step “W” (= Write); Formatting of MDS and deletion of files are not allowed 11 Step “R” (= Read only); only read operations on the MDS are allowed 0 = Siemens file handler is set up 1 = reserved for 8-E41 1 = Master 0 = Slave...
Serial either the X1 backplane connector or the 9-way Select Request interface* subminiature D connector X2. Please note: SIEMENS The Select and Re- quest lines may be omitted if only one read/write ASM 421 is being device driven from a serial in- terface.
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ASM 421 Technical Description 6GT2 097-3AH00-0DA2 ASM 421 interface modules can only be daisy-chained if they are using an RS422 or TTY interface. This allows up to 16 interface modules to be driven from one serial interface. The computer/PC must have a digital input (DI) and a digital output (DO) for each ASM 421. Mode of operation: Programming the ASM: The computer/PC “selects”...
3.10; cable and connector allocation.) Highlighted field: The standard shielded LiYCY 6 x 0.25 cable recommended by SIEMENS. This cable is available from SIEMENS under the order number 6GT2090-0A... 24 V supply to ASM 421: The maximum length of the power supply cable for the ASM 421 is restricted to 20 m.
ASM 421 Technical Description 6GT2 097-3AH00-0DA2 2.4.3 TTY cabling ASM 421 (passive) Computer (active) 1–9 b30/ –SE –EM max. length 1000 m The ASM module does not contain any power sources for energizing the active part of the TTY interface. Should, however, it become necessary for the ASM to power the interface, the ASM should be wired as follows to make it active: ASM 421 (active)
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6GT2 097-3AH00-0DA2 ASM 421 Technical Description Example of a daisy-chain configuration (see 2.4.1) ASM 421 No. 1 ASM 421 No. 2 ASM 421 No. 4 ..+24 V + SE – SE ..+24 V Computer + EM – EM Request dig.
ASM 421 Technical Description 6GT2 097-3AH00-0DA2 2.4.4 RS422 cabling ASM 421 Computer 1–9 b30/ E– D– max. length 1000 m The cable can be terminated on the receiving side with jumpers z4 – b4 and z8 – z6. This improves the interference immunity of the system particularly when long cables are used (i.e., >...
6GT2 097-3AH00-0DA2 ASM 421 Technical Description 2.4.5 V.24 cabling ASM 421 Computer 1–9 b30/ max. length 30 m V.24 control lines (e.g. DSR, DTR, RTS, CTS) are not supported by the ASM. The acknowledgement of data is handled by the procedure. 2.4.6 STG cabling ASM 421...
ASM 421 Technical Description 6GT2 097-3AH00-0DA2 2.4.7 DI/DO cabling 220 V Relay (use break-contact in load circuit of relay), horn, lamps, etc. ASM 421 24 V = – Proximity switch Error code DI 1 DI 0 = 200 mA (per DO or total current) Cable length...
6GT2 097-3AH00-0DA2 ASM 421 Technical Description Programming the ASM 421 module 3964R procedure The 3964R procedure provides secure data transmission across a point-to-point connection. Security is achieved by transmitting the data one block at a time with parity check, block check character (BCC) and acknowledgement of receipt.
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ASM 421 Technical Description 6GT2 097-3AH00-0DA2 Block Transmission Sequence: Sender Receiver t z = Watchdog timer on ASM 1st user byte 300 ms 2nd user byte Data block last user byte DLE ETX Data security To protect data against transmission errors, a parity bit is attached to each character transmitted. It is supplemented by an odd or even quantity of “ones”.
6GT2 097-3AH00-0DA2 ASM 421 Technical Description Telegram format The user communicates with the file handler via telegrams. Telegrams from the user are checked, inter- preted and processed by the file handler. The user then receives an acknowledgement telegram contain- ing user data and status information. The following schematic shows the general telegram format: Telegram heading (always present) res.
ASM 421 Technical Description 6GT2 097-3AH00-0DA2 Blocking of long data sequences Since it is not possible to work with telegrams of indefinite length, the telegram is formed into blocks, i.e. telegrams are transmitted in segments. Blocking can be used with READ, WRITE, UPDATE, QUEUE-WRITE, DIR and TRACE commands. Blocking is controlled by the parameters ADB (no.
6GT2 097-3AH00-0DA2 ASM 421 Technical Description The maximum block length (maximum length of a telegram segment) can be set using the RESET com- mand. The default value for the block length is 128. The maximum block length that can be set is 255. The blocking sequence can be aborted using the RESET command.
ASM 421 Technical Description 6GT2 097-3AH00-0DA2 3.4.1 FORMAT The FORMAT command erases the complete MDS. The directory, file allocation table (FAT) and system area on the MDS will be re-created. Some counter contents in the system area will be retained. The cur- rent counter contents can be interrogated by the MDS STATUS command.
6GT2 097-3AH00-0DA2 ASM 421 Technical Description 3.4.2 CREATE A new file is established on the MDS by the CREATE command. An entry will be made in the MDS directo- ry for each CREATE command. DIR and FAT in the MDS will be updated. Telegram to the file handler: 11/18 20/22...
ASM 421 Technical Description 6GT2 097-3AH00-0DA2 3.4.3 QUEUE-WRITE This command combines several WRITE commands into one command. This gives you the following advantages: 1. Writing of several files is faster since writing is not dependent on the serial transmission to the ASM. 2.
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6GT2 097-3AH00-0DA2 ASM 421 Technical Description Acknowledgement: CC Status ADB DBN DBL 00 xx 0000 ’Q’ 0001 00 Handling of Errors: If the file handler detects a syntax error in the structure of the transmitted file entry, the QUEUE-WRITE command is aborted with an appropriate error message. In addition, the QUEUE-WRITE command is aborted with the option = 0001 hex if the file handler determines that the file to be set up already exists.
ASM 421 Technical Description 6GT2 097-3AH00-0DA2 3.4.4 WRITE/UPDATE Telegram to the file handler: 11/18 19/21 22/24 25..254 CC CI ADB DBN DBL ’W’ xx 00 0000 ’I’ 0001 DBL File name Start addr. Length Data ’U’ User data in any format Total length of data to be written (no.
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6GT2 097-3AH00-0DA2 ASM 421 Technical Description Example: The file ‘EXAMPLE’ is to be written from position 0 with a length of 500 bytes. Assumption: the file already exists, there is enough free memory available on the MDS and the write operation will be performed with- out error.
ASM 421 Technical Description 6GT2 097-3AH00-0DA2 3.4.5 READ Telegram to the file handler: 11/18 19/21 22/24 CC CI ADB DBN DBL xx 00 0000 ’R’ ’I’ 0001 0001 File name Start addr. Length Length of file data to be read (in bytes) 000000 The presence of the file in the directory is checked.
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6GT2 097-3AH00-0DA2 ASM 421 Technical Description Example: The file ‘EXAMPLE’ is to be read from the MDS. Assumptions: the file exists and the exact length is not known. 11/18 19/21 22/24 1st telegram segment to file handler: CC CI DBN DBL File name Start addr.
ASM 421 Technical Description 6GT2 097-3AH00-0DA2 3.4.6 QUEUE-READ The QUEUE-READ command is used to read several files (max. of 15) with one command from the MDS. The complete MDS with all files can also be read as an option. Telegram to the filehandler: 11/12 13/21 22/24...
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6GT2 097-3AH00-0DA2 ASM 421 Technical Description Acknowledgment: 11/255 KK Status ADB DBN DBL Data (max. of 244 bytes) 00 xx 0000 xxxx 0001 xx xx xx xx xx xx xx xx xx The total length of all data is calculated from the sum of all DBLs in the acknowledgment telegrams.
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ASM 421 Technical Description 6GT2 097-3AH00-0DA2 Example: Five files are to be read from the MDS. 1st subtelegram on 11/12 13/21 22/24 25 to 94 filehandler: KK KI DBN DBL Option In reserve Length Data xx 00 0000 0001 0001 54H 0000 000000 000046H...
6GT2 097-3AH00-0DA2 ASM 421 Technical Description 3.4.7 DELETE The file is removed from the MDS directory. The reserved memory area is released, and becomes avail- able for other MDS operations. DELETE does not erase old user data. A delete protected file cannot be deleted: it must have its delete protection attribute removed using the ATTRIB command before it can be deleted.
ASM 421 Technical Description 6GT2 097-3AH00-0DA2 3.4.8 COVER 1. The file structure of an MDS can be protected against unauthorized access. This means that com- mands which cause changes in a checksum or create additional DIR or FAT entries can only be issued by authorized users (superusers).
6GT2 097-3AH00-0DA2 ASM 421 Technical Description 3.4.11 ASM STATUS The ASM STATUS command provides information from the file handler. The command can be used to look for errors. It shows the telegram traffic performed by the ASM 421. Telegram to the file handler: CC CI DBN DBL xx 00 0000...
ASM 421 Technical Description 6GT2 097-3AH00-0DA2 3.4.12 TRACE The TRACE command provides a physical dump of the MDS memory. It can be very useful for test pur- poses. The selected type of entry / exit checking is irrelevant as far as this command is concerned. It is always executed immediately.
6GT2 097-3AH00-0DA2 ASM 421 Technical Description 3.4.13 ATTRIB The ATTRIB command enables access rights to be assigned to individual files. Together with the access rights that can be set for each ASM with the DIL switches, each user can individually set the desired ac- cess rights.
ASM 421 Technical Description 6GT2 097-3AH00-0DA2 3.4.14 NEXT The NEXT command terminates the processing of an MDS. The command after the NEXT command will only be processed if a new MDS enters the transmission window of the SLG. Telegram to the file handler: CC CI DBN DBL xx 00 0000...
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ASM 421 Technical Description 6GT2 097-3AH00-0DA2 Acknowledgement: 11/14 CC Status ADB DBN DBL 00 xx 0000 ’X’ 0001 0001 05 Error code Proximity status (1 byte ASCII) ’0’ = no MDS in the SLG field ’1’ = MDS in SLG field The error code is normally 0000.
6GT2 097-3AH00-0DA2 ASM 421 Technical Description 3.4.16 LOAD/MOVE The LOAD and MOVE commands are optional file handler commands. These allow access times to MDS data following a cold start or restart to be optimized. The time spent reading a directory is eliminated for the first MDS to enter the field.
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ASM 421 Technical Description 6GT2 097-3AH00-0DA2 MOVE: The MOVE command provides the user with the data in the directory that has just been stored in the ASM (DIR + FAT + checksum). It can be issued by the user after bit 6 is set in the status byte of the acknowl- edgement of any command.
6GT2 097-3AH00-0DA2 ASM 421 Technical Description Telegrams from file handler In normal operation the user receives only one telegram (acknowledgement) if a command has previously been sent to the ASM. In two cases however, the ASM becomes active and sends a telegram to the user asynchronously: –...
ASM 421 Technical Description 6GT2 097-3AH00-0DA2 Cold start and restart Cold start and restart must be performed by the user and the ASM 421 in a coordinated manner. Only then can ASM and user operations be synchronized properly. Cold start and restart on the ASM 421 side: After switching on the power supply, the ASM 421 performs a comprehensive self-test.
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6GT2 097-3AH00-0DA2 ASM 421 Technical Description General evaluation of a start-up telegram by the computer: The start-up telegram can be sent from the ASM to the user at any time (e.g. following a short power fail- ure). To ensure stable operation, the user must always be in a position to accept and evaluate the incom- ing telegram.
ASM 421 Technical Description 6GT2 097-3AH00-0DA2 Checking entry and exit of MDS in SLG transmission window This chapter describes various procedures for recognizing when an MDS is within range of an SLG. The user can use the procedure most appropriate for the application with the RESET command: EAKO (see section 3.4.15).
6GT2 097-3AH00-0DA2 ASM 421 Technical Description MDS recognition by field scanning EAKO = ’0’ How field scanning works The SLG scans the surrounding area for the presence of a data carrier. If the file handler recognizes a data carrier, the ANW bit will be set and a Z telegram sent to the user. After the MDS has left the transmission window, the ANW bit will be reset and a Z telegram will be sent to the user, while the SLG scans the field for the next MDS.
ASM 421 Technical Description 6GT2 097-3AH00-0DA2 Without entry/exit monitoring EAKO = ’1’ Schematic layout: É É É É É É É É É É É É É É É É É É É É É É É É É Direction of movement of É...
6GT2 097-3AH00-0DA2 ASM 421 Technical Description MDS control using field scanning and 1 DI EAKO = ’2’ Schematic layout: É É É É É É É É É É É É É É É É É É É É É É É É É Direction of movement of É...
ASM 421 Technical Description 6GT2 097-3AH00-0DA2 MDS control using 2 DIs EAKO = ’3’ Schematic layout: Transmission window; no significance for entry/exit monitoring Direction of movement of É É É É É É É É É É É É Prox. switch Prox.
6GT2 097-3AH00-0DA2 ASM 421 Technical Description Without entry/exit monitoring EAKO = ’4’ É É É É É É É É É É É É É É É É É É É É Direction of É É É É É movement of É...
ASM 421 Technical Description 6GT2 097-3AH00-0DA2 Special Operating Mode (Test Operation) EAKO = ’5’ É É É É É É É É É É É É É É É É É É É É Direction of É É É É É movement of É...
6GT2 097-3AH00-0DA2 ASM 421 Technical Description Diagram showing possible MDS states at an SLG The following codes are used in the diagram on the following page: MDS absent new/next MDS present current or old (no longer current) MDS present Command present (the user has already transmitted an MDS command to the MDS) Command not present (the ASM is not processing an MDS command from the user) Command in progress (a command is now being executed) “Next MDS bit”...
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ASM 421 Technical Description 6GT2 097-3AH00-0DA2 Ç Ç Ç Ç Ç Ç Ç Ç NEXT ackn. NEXT Ç Ç Ç Ç RESET no MDS at SLG / EAKO 1,4 COMMAND ARRIVES Ç Ç Ç DEPARTS ARRIVES NEXT DEPARTS Ç Ç Ç Ç Ç...
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6GT2 097-3AH00-0DA2 ASM 421 Technical Description EAKO = 1; The user assumes control of the MDS. No MDS is in the transmission window of the SLG on restart. Processing of the MDS takes place statically. The process consists of the commands: read “file A”, read “file B”...
ASM 421 Technical Description 6GT2 097-3AH00-0DA2 System and transmission times The following diagram shows the various timings inherent in a system: ASM 421 Internal PC times: Serial data transmission Data transmission between file handler File handler processing from/to ASM 421: and MDS: time: –...
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6GT2 097-3AH00-0DA2 ASM 421 Technical Description Example: You want to know how much time elapses from the start of a read operation until the data is in the PC memory. The file to be read has a length of 350 bytes and is to be transmitted in 2 blocks. The maximum block length to the PC is 255 bytes.
ASM 421 Technical Description 6GT2 097-3AH00-0DA2 Troubleshooting and error messages An error message from the file handler always has the same format. The presence of an error is always indicated in the status byte (5th byte) of the acknowledgement telegram. It is 4 bytes long and in ASCII format.
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6GT2 097-3AH00-0DA2 ASM 421 Technical Description The following table contains a summary of all the errors from the ASM 421: flashes of Kind of Error messages from the file handler red LED error A0 06 Unknown error, the command code CC is invalid A0 11 DBN not equal to 1 in first command block;...
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ASM 421 Technical Description 6GT2 097-3AH00-0DA2 Full error description A0 06: The command code for the started command is not valid (not defined). The correct CC must be entered (see section 3.4). A0 11: – for the first command block: DBN (= byte 8/9 in the telegram) does not have the value 0001.
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6GT2 097-3AH00-0DA2 ASM 421 Technical Description C0 02: Memory error message from MDS. The MDS has not yet been written or has lost its memory content due to battery failure (not with EEPROM MDS). Therefore: – change the MDS (if the battery monitoring bit is set) –...
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ASM 421 Technical Description 6GT2 097-3AH00-0DA2 C0 14: The MDS memory cannot be written – the MDS has a smaller memory than specified in the FORMAT command, i.e. enter the correct parameters for this type of MDS – the MDS memory is defective –...
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6GT2 097-3AH00-0DA2 ASM 421 Technical Description D0 23: COVER command: the MDS name specified in the command does not correspond to the actual MDS name. E0 01: – the type of MDS present at the SLG does not correspond to the ECC operating mode se- lected.
Should you not be in possession of the MOBY catalog, it can be Sollten Sie nicht im Besitz des MOBY-Katalogs sein, so kann er obtained through your local Siemens office. über jede örtliche SIEMENS-Niederlassung bestellt werden. 6GT2 002-0DA00 ASM 421 / V.24 Subject to change without notice! –...
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Si vous ne disposez pas ou du catalogue MOBY, ce peuvent être com- Se non doveste essere in possesso del catalogo MOBY, potete ordi- mandés auprès de votre agence SIEMENS. narlo presso qualsiasi filiale SIEMENS di zona. Español Svensk Varning Precaución...