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The Command interface in the 4000 series

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1 The Command interface in the 4000 series
The 4000 series instrument may receive "commands" over any of its network (DeviceNet, Ethernet/IP) interfaces. A "command" in the 4000 series consists of a four-byte "command number", which it receives through its network input data. The instrument responds with a four-byte response. To read the value of any parameter, send the four byte PARAMETER ID. In both DeviceNet and Ethernet/IP, the byte order is LITTLE ENDIAN, that is, least significant byte first. The instrument will then return the value of the parameter, which will be either an integer or a floating point value. You may find the PARAMETER IDs on the OPERATION/DIAGNOSTICS/PARAMERS web page. To write the value of a parameter is a little more complicated, because the PARAMETER ID is 4 bytes long, and the parameter value is also 4 bytes long if it is a floating point number, but each command is only 4 bytes long. Most integer valued parameters are only 2 bytes long. Also, the most significant two bytes of the PARAMETER ID is usually zero. To set the value of a two byte parameter with a two byte PARAMETER ID, send these four bytes: byte 0: the least significant byte of the PARAMETER ID byte 1: the next byte of the PARAMETER ID, but with the highest order bit set. bytes 2,3: the value you want to set the parameter to. For example, to set the value of NumAverages to 3, send this command: <0x8005><0x0003> Here, the <0x0005> is the lowest 2 bytes of the PARAMETER ID for NumAverages, which becomes 0x8005 after we set the most significant bit, and <0x0003> is the value you want to set the parameter to. If the parameter is 4 bytes long, as all floating point values are, you must first set the upper 2 bytes. There is a special parameter ID (0x4000, or 0xC000 with the upper bit set) for doing this. Also, if the upper two bytes of the PARAMETER ID are not zero, use the special parameter ID (0x4001, or 0xC001 with the upper bit set) to set the upper two bytes. All write commands are 1-shots The first 2 bytes of the response to a write command are an echo of the first two bytes of the command. The next 2 bytes are an echo of the next two bytes. If the PARAMETER ID is not valid, the instrument will return 4 zero bytes. Parameter writing example: setting Setpoint 2 Target to 1.0 Setpoint 2 Target has a PARAMETER ID of 0x (hexadecimal). The number 1.0 in hexadecimal is 0x3F Step 1: Set the upper two bytes of the parameter value with the command <0xC000><0x3F80> Step 2: Set the upper two bytes of the parameter ID with the command <0xC001><0x0001> Step 3: Write the Setpoint 2 Target with the command <0x8012><0x0000> This is an excerpt from the Technical Paper on mapping found in the online browser of the HI 4050 unit. You can find this by clicking on the link to “A Technical Paper on Mapping” found on your unit’s mapping page.

2 Setting up the command interface in mapping:
Use an equation of the form CMD0 = (in_table)*(out_table) In_table is an input table, defining where the command is written. Out_table defines where the reply data is written. Example: CMD0= DSI0*DSO0 This equation says the command will be written to the DeviceNet input table, at word offset 0, and the reply data is written to the DeviceNet output table, at word offset zero. The upper two bytes of the PARAMETER ID (JSO15) and the upper two bytes of the parameter value (JSO14) can also be mapped. By doing this, you can set 4 byte parameter values using a single command, rather than the 3 commands required using only the CMD0 command.

3 HI 4050 INTEGRATED TECHNICIAN OVER MODBUS MAPPING
Mapping needed JSO15 = +MSI2 CMD0 = +MSI0 * +MSO0 The mapping CMD0 = MSI0 * MSO0 is the mapping for the command interface. This example used input word 0 as the starting location of my 4 bytes input, but this could be any word location being used as the input to the unit. The input words 0 & 1 in the control system computer will be where the command is set into the unit and words 0 & 1 on the output is where the data will go to the HI 4050. JSO15 is the location where the upper (MSW) 2 bytes of the parameter ID is set. Since all the parameter ID’s are 4 bytes long, we need to insure this location contains the upper 2 bytes of the parameter we want to read. If this is not set correctly, we will get some other, unknown data. Since all the Integrated Technician data is read only, we will not need to have mapping for JSO14 for the upper 2 bytes of the parameter value being written.

4 Parameter ID Numbers All parameter ID’s are 4 bytes long.
The lower 2 bytes of all parameter ID’s is: 020A hex Mapped to MSI0 The upper 2 bytes of all parameter ID’s will range from: 0000 to 0018 hex Mapped to MSI2 All of the parameter ID’s for the Integrated Technician data will have the same value for the lower 2 bytes. This will be a hex value of 020A. This 2 byte value will be placed into the 1st word of the Command interface word to the unit. The upper 2 bytes of parameter ID will need to be written into the JSO15 location. Between these two locations, the unit will have the entire 4 bytes of the parameter ID, and will send the correct data.

5 Parameter ID Numbers (hex)
Weight on 1st j-box channel 000D 020A MV on 3rd j-box channel A Weight on 2nd j-box channel 000E 020A MV on 4th j-box channel A Weight on 3rd j-box channel 000F 020A Return to zero combined A Weight on 4th j-box channel A Return to zero on 1st j-box channel A IT j-box switches A Return to zero on 2nd j-box channel A C2 load cells found at calibration A Return to zero on 3rd j-box channel A MV/V on 1st j-box channel A Return to zero on 4th j-box channel A MV/V on 2nd j-box channel A Turn off IT test A MV/V on 3rd j-box channel A Turn on IT test for 1st channel of j-box 000A 020A MV/V on 4th j-box channel A Turn on IT test for 2nd channel of j-box 000B 020A MV on 1st j-box channel A Turn on IT test for 3rd channel of j-box 000C 020A MV on 2nd j-box channel A Turn on IT test for 4th channel of j-box Here is a list of all the IT parameter ID values and the parameter description. In the following pages we show a representative few of the commands. We do no show you every command. By substituting the correct command into the MSW of PARAM ID, selected test will be preformed. If you do not have an IT junction box, then you will not be able to get the individual returns as listed above for each parameter ID. You can run the overall tests and receive the overall condition of the scale.

6 READ and WRITE as viewed from the control system.
MSW of PARAM ID 1ST WORD OF CMD0 2ND WORD OF CMD0 WRITE DATA 2ND WORD OF CMD0 RETURN 1ST WORD OF CMD0 RETURN READ DATA 0016 0000 020A (Hex Format) READ and WRITE as viewed from the control system. (floating point format) An example of running the IT functions through mapping: All values shown will be in hex. Here we are showing the writing of the parameter ID A. This is the “DWELL_CHAN_1”. This will turn ON the IT functions mode. The return from this command will be zero. Once placed into the IT mode, the j-box information to the unit is not the normal weight information. It will only be the input from the load cell under test at that time. The weight reading will not be normal, “Do not run these tests while in operation”. Once you have changed the unit into the IT mode, you can change the MSW of the parameter ID to select different data and tests.

7 (floating point format)
MSW of PARAM ID 1ST WORD OF CMD0 2ND WORD OF CMD0 WRITE DATA 2ND WORD OF CMD0 RETURN 1ST WORD OF CMD0 RETURN READ DATA 0000 020A 4170 (Hex Format) (floating point format) After entering into the IT mode, apply a parameter ID of A, this will return the weight on the first load cell (position 1 in the J-box). This will be in floating point format and take up all four bytes of the return. In this example the return is 15.0.

8 (floating point format)
MSW of PARAM ID 1ST WORD OF CMD0 2ND WORD OF CMD0 WRITE DATA 2ND WORD OF CMD0 RETURN 1ST WORD OF CMD0 RETURN READ DATA 0001 0000 020A 4120 (Hex Format) (floating point format) Change the MSW of the parameter ID to 0001 and display the weight on the load cell in the second position of the j-box. In this example it is returning a value of 10.0.

9 (floating point format)
MSW of PARAM ID 1ST WORD OF CMD0 2ND WORD OF CMD0 WRITE DATA 2ND WORD OF CMD0 RETURN 1ST WORD OF CMD0 RETURN READ DATA 0009 0000 020A 3F80 (Hex Format) (floating point format) Here we have switched to read the parameter ID A, the mv/v reading from the load cell in the 3rd position on the J-Box. In this example, the mv/v reading is 1.0mv/v.

10 (floating point format)
MSW of PARAM ID 1ST WORD OF CMD0 2ND WORD OF CMD0 WRITE DATA 2ND WORD OF CMD0 RETURN 1ST WORD OF CMD0 RETURN READ DATA 000D 0000 020A 40A0 (Hex Format) (floating point format) The HI 4050 does not read the excitation voltage, and must rely on the voltage being correct at 5V. The mv readings will be the mv/v reading multiplied by 5. The mv readings from the load cell in the 3rd position in the j-box would be the mv/v reading times 5. In this case, since the mv/v reading we got was 1.0, the mv reading is 5.0.

11 (floating point format)
MSW of PARAM ID 1ST WORD OF CMD0 2ND WORD OF CMD0 WRITE DATA 2ND WORD OF CMD0 RETURN 1ST WORD OF CMD0 RETURN READ DATA 000F 0000 020A 0001 (Hex Format) (floating point format) Return to zero combined. If all the load cells are within tolerance of zero, then the least significant bit of the first word will be on. The tolerance is the zero tolerance plus the motion tolerance.

12 (floating point format)
MSW of PARAM ID 1ST WORD OF CMD0 2ND WORD OF CMD0 WRITE DATA 2ND WORD OF CMD0 RETURN 1ST WORD OF CMD0 RETURN READ DATA 0013 0000 020A 0001 (Hex Format) (floating point format) Individual return to zero test for the 4th load cell position in the j-box. If this is within the tolerance, then it will have the least significant bit of the first word set. If out of tolerance, it will not be set.

13 (floating point format)
MSW of PARAM ID 1ST WORD OF CMD0 2ND WORD OF CMD0 WRITE DATA 2ND WORD OF CMD0 RETURN 1ST WORD OF CMD0 RETURN READ DATA 0014 0000 020A (Hex Format) (floating point format) Once we are done checking the IT functions, we must take the unit out of IT mode. With parameter ID A, we select DWELL_NO_CHAN, which turns off the IT functions. This will put the j-box back to normal and the unit will get inputs from all load cells and display weight in a normal manner.

14 (floating point format)
MSW of PARAM ID 1ST WORD OF CMD0 2ND WORD OF CMD0 WRITE DATA 2ND WORD OF CMD0 RETURN 1ST WORD OF CMD0 RETURN READ DATA 0000 (Hex Format) (floating point format) Once you have written the parameter ID for the DWELL_NO_CHAN to take the unit out of the IT mode, you would want to remove this command from the command interface also. If you do not remove the DWELL_NO_CHAN from the command interface, then the unit cannot be placed into the IT test mode from the front panel, as every time you try to place it into the test mode, it would be overwritten with the DWELL_NO_CHAN command to remove it from this mode.


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