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USING THE V180 IN VME-BASED SYSTEMS and PLCs
1. INTRODUCTION
The V180 electrical measurement module allows VME-based systems to measure AC electrical parameters such as true RMS voltage, current, power, and energy. The V180 is functionally identical to the Highland model AT180 metering module, except that is packaged in the VME format and is addresses as a block of 16-bit registers in the VME addressing space.
This note describes certain features relevant to using the module in common VME system applications.
Refer to the V180/AT180 users manual for an introduction to the general characteristics of the V180/AT180 products.
2. VME COMPATIBILITY
The V180 is a '6U' (dual height), single width VME module and complies with the IEEE 1014-1987 VME specification. The module occupies 2048 16-bit registers in the short (16-bit) addressing space of the VME bus; it is an "A18/D16/ D08(EO)"-type module. The V180 uses the P1 VMEbus connector only. It requires only the standard +5, +12, and -12 volt power supply voltages, and does not interrupt. All interrupt and bus grant lines are passed on by the V180.
Field I/O is via a front-panel D37 connector which connects, via a suitable cable, to the C760 termination panel. The D37 connector shell is electrically continuous with the front panel, and the front panel is NOT connected to the VMEbus common.
3. INSTALLATION
The V180 may be installed in any 6U VME card cage. Before installing the module, read and follow the steps below.
1. If a battery protector is installed (a strip of blue plastic under the upper leaf of the battery holder), remove it.
2. Set all four sections of the maintenance dipswitch ("S6 TEST") to the OFF position; press the lower sides of the switch rockers (near the word "OFF") with a straightened paper clip or toothpick.
3. Set the port address dipswitch ("S4 ADD") to the desired VME Short I/O VME Space (address modifiers 29H and 2DH) base address. Before setting this switch, determine the I/O addresses of all devices on your computer's bus and select an unused block of 2KB space for the V180 to use. The ADDRESS dipswitch can be used to select any address from 0000 to F800 hex. The first five of the eight switches are functional and they each select one bit for the address comparator, as shown in the following table:
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To select the standard address C000 hex, turn ON sections 1, and 2. The V180 may be inserted into any standard VME crate or VME-compliant programmable logic controller.
ALWAYS TURN OFF CRATE POWER BEFORE INSTALLING OR REMOVING THE MODULE. ALWAYS SECURE THE FRONT-PANEL HOLD-DOWN SCREWS.
After securing the module, connect and secure the front-panel I/O cable and connect the other cable end to the termination panel.
THE TERMINATION PANEL AND THE VME CARD CAGE MUST BOTH BE SECURELY GROUNDED.
When the VME crate is powered up, the front-panel PASS/FAIL LED should initially illuminate red and, after the self-test sequence passes (in about 1 second), should turn green. The SCAN LED should then blink once per second, and the blue VME led should light whenever the module is addressed by the VME bus.
If you are using the PV software (i.e., you are operating in a XYCOM XVME-674 or through a BIT3 Model 406) the CONFIG.180 file should be edited to identify the device as a V180, indicate its base address, and to include comments on its function. (See Section 5 of the AT/V180 manual.)
4. PROGRAMMING
4.1 PARAMETER SETS
The PARAMETER SET is a 'setup file' which configures the V180 for a particular measurement situation. The parameter set editor source code PARSET.C is provided. There are three ways a parameter set may be installed in a V180:
A. DEFAULT PARAMETER SET
All V180s include the standard default parameter set in the on-board EPROM, and install this set on 'cold' powerup. The configuration of the default parameter set is noted in the PARSET.C file. The INSTALL DEFAULT PARAMETER SET or REINITIALIZE commands may be used to ensure that the default set is installed. To review the default parameter set, run the PARSET.EXE program on an MS-DOS compatible PC; PARSET, when started, initially assumes the default set.
B. CUSTOM EPROM PARAMETER SET.
Users may, if desired, create a custom parameter set using the PARSET.EXE program. This set may be saved as a disk file and sent to Highland, where it may be included in a custom EPROM set. If such a parameter set is installed in EPROM, the V180 will use it by default in preference to the default parameter set. The INSTALL CUSTOM EPROM PARAMETER SET command will force reinstallation of this setup if the custom set exists in EPROM.
C. LOADING A PARAMETER SET FILE.
A parameter set may be created by the PARSET.EXE program (source code PARSET.C is provided) and loaded into the V180 over the VME bus. The parameter set will be saved by PARSET as an MS-DOS compatible (binary) file of 768 words (1536 bytes) length. It may be written to the V180 using the INSTALL PARAMETER SET command, described in AN3.
If the VMEbus controller is capable of running MS-DOS, the B180.EXE program (source code B180.BAS provided) may be used to install the parameter set file to the module. B180 includes drivers for the XYCOM and BIT3 PC-to-VME interfaces, and can be easily modified for other memory-mapped VME interfaces. If the VME master is not DOS compatible, users will need to write a short routine to load parameter set files into the V180.
The algorithm used to download a Parameter Set to a V180 module is:
1.Write the Parameter Set (768 words long) created by PARSET>EXE to the Dual Port Memory (DPM) of the V180 module starting at Base Address + 100 hex.
2.Write the password 4854 hex to the PASS register (Base Address + B hex )
3.Write the command code WPS ( 5 hex ) to the CMD (Base Address + 9 hex) register
4.Read the CMD (Base Address + 9 hex) register; when its low byte goes to zero, the command has been executed. If the high byte of CMD is then non-zero, a command error has ocurred.
When using B180, edit the CONFIG.180 file to include a 'unit' line which notes the presence of the V180 and its hex address in the VME A16 space. The VME controller line in CONFIG.180 (the line beginning with a star) should also be edited to specify the interface type (XYCOM or BIT3) and its memory window segment address in hex. The standard CONFIG.180 file includes examples of these lines.
4.4 READING REALTIME DATA
If the VME system can run the B180.EXE program, it may be used to display realtime data from the V180.
For users who cannot used B180, application note AN3 details reading realtime data from a V180 module at the register level. As it notes, the module will present normalized realtime values as 16 and 32-bit words, beginning at the module's base VME address. Multiple VME masters may access the V180 realtime data concurrently, but should double-read 32-bit values to verify coherency. |
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