User Manual PDF File

VM8PF
Programmable
Filter
8 Channel VME Module
USER MANUAL
1. Introduction
2. Unpacking and Inspection
3. Hardware Configuration
4. Board Installation
5. I/O Connections and the Front Panel
5.1 Front Panel Layout
5.2 Connector/Cable Information and I/O Connections
6. Software Overview
7. Adjusting Channel DC Offset
8. Troubleshooting and Technical Support
9. Warranty Information
APPENDICES
A. Functional Description and Register Level Programming
B. VM8PF Specifications
C. VM8PF Ordering Guide
We hope the information given here will be helpful. The information is based on data and our best knowledge, and we consider the information to be true and accurate. Please read all
statements, recommendations or suggestions herein in conjunction with our conditions of sale which apply to all goods supplied by us. We assume no responsibility for the use of these
statements, recommendations or suggestions, nor do we intend them as a recommendation for any use which would infringe any patent or copyright.
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1784 Chessie Lane., Ottawa, IL 61350 • Tel: 800/252-7074, 815/434-7800 • FAX:815/434-8176
e-mail: [email protected] • Web Address: http://www.freqdev.com
VM8PF
Programmable
Filter
8 Channel VME Module
1.0 Introduction
Frequency Devices' Model VM8PF comprises a family of VMEbus filter boards offering eight channels of
software programmable high performance linear analog filtering in a single width B-size (6U) VME form
factor. VM8PF boards receive up to eight high level differential signal inputs through a shielded front panel
connector and provide signal buffering and software programmable filtering for each channel. A second
connector is wired in parallel with the input connector to facilitate filter bypassing. VM8PF boards may be
configured with 824 Series four-pole or 828 Series eight-pole filters and with high pass and/or low pass
transfer functions allowing user to externally cascade filters into band-pass configurations. The boards
conform to VME revision C.1 as an A16/D16 Slave. Appendix A provides a functional overview of the
VM8PF boards.
2.0 Unpacking and Inspection
Before unpacking the VM8PF shipping container, carefully inspect the exterior of the package for evidence
of damage. After noting areas of possible shipping damage, open and unpack the shipping container, being
careful to preserve the container and packing materials in case they are needed later.
CAUTION
The VM8PF Board is sensitive
to STATIC ELECTRICITY. Use proper GROUNDING TECHNIQUES
when handling the board.
Carefully remove the VM8PF board from its anti-static bag and visually inspect for evidence of damage. If
the board appears to be damaged in any way, notify the shipping carrier.
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e-mail: [email protected] • Web Address: http://www.freqdev.com
VM8PF
Programmable
Filter
8 Channel VME Module
3.0 Hardware Configuration
Once the VM8PF VMEbus board has been removed from its anti-static bag and carefully inspected for
damage, you are ready to configure the board's base address for your particular system. The Base Address
is the only hardware configuration on the VM8PF board. The factory set Base Address is F000 (hex).
CAUTION: The VM8PF Board is sensitive
to STATIC ELECTRICITY. Use proper GROUNDING TECHNIQUES
when handling the board.
To reconfigure the VM8PF base address, lay the board flat as shown in Figure 3-1.
The ten-position jumper block shown in Figure 3-1 is used to set the board's base address in A16 address
space. A VM8PF board occupies a 64-byte block in A16 address space and may be configured on any 64byte boundary. The ten jumper positions correspond to address lines A15 through A06. As shown in Figure
3-1, jumper position 06 corresponds to address line A06, jumper position 07 corresponds to A07, etc. An
installed jumper sets logic '1' while a missing jumper sets logic '0'.
After the board's base address has been configured, the VM8PF is ready for installation in a VME system.
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e-mail: [email protected] • Web Address: http://www.freqdev.com
VM8PF
Programmable
Filter
8 Channel VME Module
Figure 3-1
VM8PF Base Address Configuration Jumpers
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e-mail: [email protected] • Web Address: http://www.freqdev.com
VM8PF
Programmable
Filter
8 Channel VME Module
4.0 Board Installation
Frequency Devices' Model VM8PF eight channel VMEbus filter boards conform mechanically, in every
respect, to the single width VME "B" size (6U) form factor. Installation of a VM8PF board into a standard
VME mainframe can proceed exactly as for any other standard single width "B" size (6U) VME board.
CAUTION
The VM8PF Board is sensitive
to STATIC ELECTRICITY. Use proper GROUNDING TECHNIQUES
when handling the board.
The VM8PF board may be installed in any available mainframe slot except Slot 0. The board does not use
VMEbus interrupts or bus mastering capabilities, but passes all VMEbus daisy chained signals
automatically.
The major considerations in locating the VM8PF board in the mainframe are for EMI and I/O signal
cabling. To minimize interference from other boards in the system, it is good practice to keep one or more
empty slots between analog signal conditioning boards and high speed digital boards in the system. When
cabling the system, it is desirable to keep the analog signal cabling as short as possible and physically
located away from high speed digital cabling and high voltage switching lines.
5.0 I/O Connections and the Front Panel
The following information is provided to assist the user/integrator in installing and interconnecting a
VM8PF board into a VME system.
5.1 Front Panel Layout
Figure 5-1 shows the layout of the VM8PF front panel. The following sections provide detailed information
about connectors, pin-out, and cabling. There are no front panel indicators or controls on the VM8PF.
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VM8PF
Programmable
Filter
8 Channel VME Module
Figure 5-1
VM8PF Front Panel
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VM8PF
Programmable
Filter
8 Channel VME Module
5.2 Connector/Cable Information and I/O Connections
The Analog Input connector is a 25-pin female "D" shell connector located near the top of the front panel.
The Bypass connector is a 25-pin male “D” shell connector located below the Input connector. The Bypass
connector is wired in parallel with the Input connector and may actually be used as the Input connector.
Analog Input and Bypass connections are as follows:
INPUT
BYPASS
FUNCTION
DB25 FEMALE
DB25 MALE
Channel 0 HI
2
12
Channel 0 LO
15
24
Signal GND
14
25
Channel 1 HI
16
23
Channel 1 LO
4
10
Signal GND
3
11
Channel 2 HI
19
20
Channel 2 LO
7
7
Signal GND
6
8
Channel 3 HI
5
9
Channel 3 LO
18
21
Signal GND
17
22
Channel 4 HI
8
6
Channel 4 LO
21
18
Signal GND
20
19
Channel 5 HI
22
17
Channel 5 LO
10
4
Signal GND
9
5
Channel 6 HI
25
14
Channel 6 LO
13
1
Signal GND
12
2
Channel 7 HI
11
3
Channel 7 LO
24
15
Signal GND
23
16
Refer to Figure 5-1 for connector orientation. The mating connectors are the Amp HD-20 family.
Frequency Devices recommends that input and bypass signals be wired using cable consisting of
individually shielded twisted pairs of #22 AWG stranded wire.
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VM8PF
Programmable
Filter
8 Channel VME Module
The Analog Output connector is a 25-pin female "D" shell connector located near the bottom of the front
panel. Analog Output connections are as follows:
FUNCTION
Channel 0
Signal GND
Channel 1
Signal GND
Channel 2
Signal GND
Channel 3
Signal GND
Channel 4
Signal GND
Channel 5
Signal GND
Channel 6
Signal GND
Channel 7
Signal GND
OUTPUT
DB25 FEMALE
15
14
4
3
7
6
18
17
24
23
21
20
13
12
10
9
Refer to Figure 5-1 for connector orientation. The mating connector is the Amp HD-20 family. Frequency
Devices recommends that output signals be wired using cable consisting of individually shielded twisted
pairs of #22 AWG stranded wire.
8
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e-mail: [email protected] • Web Address: http://www.freqdev.com
VM8PF
Programmable
Filter
8 Channel VME Module
6.0 Software Overview
A two-register read/write programming interface makes the VM8PF family of VMEbus filter boards
extremely easy to program. Appendix A of this User's Manual, beginning on Page 14, provides detailed
information for programming the VM8PF from the VMEbus and may be used as the basis for OS-specific
driver development.
7.0 Adjusting Channel DC Offset
The VM8PF module hardware includes on board trim potentiometers, one for each channel, to adjust DC
offset voltage at the channel's output. The offset adjust pots are accessible from the component side of the
board. A small flathead screwdriver, or similar adjustment tool, is required to make offset adjustments.
CAUTION
The VM8PF Board is sensitive
to STATIC ELECTRICITY. Use proper GROUNDING TECHNIQUES
when handling the board.
Adjusting the zero offset voltage must be done with the board powered and only after at least a 20 minute
warm-up period. The user must provide an external means for obtaining precise zero volts input and for
measuring channel output voltage.
Figure 7-1 shows the location of the offset adjustment potentiometers and identifies which adjustments
correspond to which channels.
Turning an adjustment potentiometer clockwise increases the output voltage; counter clockwise causes the
output voltage to go more negative. Adjustment range is approximately +/-25 millivolts.
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VM8PF
Programmable
Filter
8 Channel VME Module
Figure 7-1
VM8PF Zero Adjustment Potentiometers
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e-mail: [email protected] • Web Address: http://www.freqdev.com
VM8PF
Programmable
Filter
8 Channel VME Module
8.0 Troubleshooting and Technical Support
If you have difficulty installing the VM8PF board, or if the board fails to operate properly, contact
Frequency Devices for technical assistance. Technical assistance is available weekdays 8:00 AM to 4:30
PM Central time at 815-434-7800 or 800-252-7074. Inquiries may also be faxed to 815-434-8176 or
emailed to [email protected].
If you need to contact Frequency Devices in writing, our address is:
1784 Chessie Lane
Ottawa, IL 61350
Attn: Customer Service
Please have the following information handy prior to contacting Frequency Devices for assistance:
Model Number and Serial Number
Purchase Order Number
Your "Bill To" and "Ship To" addresses
If Frequency Devices determines the board must be returned to the factory, you will be issued a Return
Material Authorization (RMA) number. Use this number on all shipping containers, repair purchase orders,
and shipping documents. DO NOT ATTEMPT TO RETURN BOARDS WITHOUT FIRST OBTAINING
AN RMA NUMBER.
CAUTION
The VM8PF Board is sensitive
to STATIC ELECTRICITY. Use proper GROUNDING TECHNIQUES
when handling the board.
11
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e-mail: [email protected] • Web Address: http://www.freqdev.com
VM8PF
Programmable
Filter
8 Channel VME Module
9.0 Warranty Information
Unless otherwise specified in writing by FDI, all FDI products sold hereunder are warranted against defects
in workmanship and material under normal use and service for a period of one (1) year from the date of
delivery, except that, where applicable liability for defective components purchased by FDI and are resold
to the purchaser hereunder shall conform and be limited to the obligations prescribed by the original
manufacturer’s warranties applicable to such components.
All warranties hereunder are contingent upon proper use in the application for which the product was
intended and do not cover products which have been modified or repaired without FDI approval or which
have been subjected to neglect, accident, improper installation or application or on which the original
identification marks have been removed or altered. These warranties will not apply if adjustment, repair or
parts replacement is required because of accident, neglect, misuse, power failure, transportation or other
causes other than ordinary use.
FDI's responsibility under the above warranty shall be limited to the repair or replacement, at FDI's option,
free of charge to the purchaser, of any component, which fails during the one-year period; provided that the
purchaser has promptly reported such failure to FDI in writing and FDI has, upon inspection, found such
components to be defective. The purchaser must obtain shipping instructions for the return of any item
under this warranty provision and compliance with such instructions shall be a condition of this warranty.
EXCEPT FOR EXPRESS WARRANTIES STATED ABOVE, FDI DISCLAIMS ALL WARRANTIES
WITH REGARD TO THE PRODUCTS SOLD HEREUNDER, INCLUDING ALL IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS.
Limitation of Liability
Expressed warranties stated herein are in lieu of all obligations or liabilities on the part of FDI for damages,
including but not limited to consequential damages arising out of or in connection with the use or
performance of the product.
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e-mail: [email protected] • Web Address: http://www.freqdev.com
VM8PF
Programmable
Filter
8 Channel VME Module
Appendix A
Functional Description and Register Level Programming
BASIC OPERATION
With the VM8PF VMEbus filter board; the user can set filter cutoff frequency independently for each
channel. The user can also read back individual filter cutoff frequency settings. This bi-directional access
is especially useful when building fault tolerant systems, for diagnosing system failures, for debugging
newly developed systems, and for constructing reliable test header files.
Since the filters are galvanically isolated from system ground and the filters' logic system is based on 15
Volt CMOS levels, an opto-isolated serial communications channel is used to transfer data to/from the
filters one channel at a time. Figure A-1 is a block diagram of the isolated side of the serial channel.
The serial channel incorporates some features that are especially important when providing precision, low
noise signal conditioning. For example, when the board is not being accessed (the normal case during a
test) the serial channel is entirely static and is gated into a low power state (no isolator power consumption
on the filter side). When the board is accessed to set or read back a cutoff frequency only the channel being
accessed is clocked, so the other channels on the board see no logic transitions that could inject noise or
induce DC offsets.
The isolated serial channel is slow compared to VMEbus transfer rates. Rather than hold the VMEbus
while cutoff data is serialized and transferred over the isolation barrier, the VM8PF board uses a BUSY flag
interlock while data transfer to/from the selected channel is taking place.
To write cutoff data to a filter channel the user first reads the Channel Address Register (CHADR, Base+0)
and tests its BUSY bit to see if the serial interface is busy. If BUSY is set the user can go on to other things
and come back to the board later, or the user can poll CHADR, waiting for BUSY to clear. Once BUSY is
found clear the user writes the desired channel address to CHADR (making sure to write '0' to the BUSY
bit) and then writes the cutoff data to the Data Register (DATA, Base+2). The VM8PF automatically sets
the BUSY bit in CHADR, serializes and transfers the new data, and then clears BUSY once transfer is
complete. The serial channel will be busy for approximately 32 microseconds.
To read cutoff data from a filter channel the user first reads the Channel Address Register (CHADR,
Base+0) and tests its BUSY bit to see if the serial interface is busy. If BUSY is set the user can go on to
other things and come back to the board later, or the user can poll CHADR, waiting for BUSY to clear.
Once BUSY is found clear the user writes the desired channel address to CHADR while simultaneously
writing the BUSY bit to '1'. The serial interface accesses cutoff data from the selected channel and clears
the BUSY bit in CHADR when the requested data is available in DATA (approximately 32 microseconds
later). The user waits for BUSY to clear and then reads DATA.
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VM8PF
Programmable
Filter
8 Channel VME Module
Please note that, as is always the case when a flag can be controlled by two or more systems, instructions
that generate read/modify/write cycles (or read followed by write cycles) should be avoided when testing
the state of the BUSY bit. The safest way to test BUSY is to read CHADR into a local register and then test
the state of the BUSY bit in the registered copy.
Cutoff data may be interpreted as the following:
Fword = ( FC / FB ) – 1 , where Fword is the binary representation of the resultant frequency, FC is the
cutoff frequency, and FB is the base frequency of a specific filter module. For example, in an 828L8E-2, the
base frequency is 1Hz, whereas a 828L8E-5 has a base frequency of 200Hz.
The following example shows how to set the VM8 channel 3, an 838L8E-2 filter module, to a cutoff
frequency of 64Hz. It assumes a VM8 base address of (2000)x:
- Find: Fword = (64 / 1) – 1 = (63)d
- Determine Fword binary word (8 bits) value: (0011 1111)b
- Determine channel binary representation (3 bits) value: (011)b
- Read the CHADR in (2000)x , and tests its BUSY bit to see if the serial interface is busy. Wait
for BUSY to clear.
- Write the channel address to CHADR (2000)x: (0000 0000 0000 0011)b
- Write the cutoff data to DATA (2002)x: (0000 0000 0011 1111)b.
This example shows how to set the VM8 channel 6, an 838L8E-5 filter module, to a cutoff
frequency of 200Hz. It assumes a VM8 base address of (4000)x:
- Find: Fword = (200 / 200) – 1 = (0)d
- Determine Fword binary word (8 bits) value: (0000 0000)b
- Determine channel binary representation (3 bits) value: (110)b
- Read the CHADR in (4000)x , and tests its BUSY bit to see if the serial interface is busy. Wait
for BUSY to clear.
- Write the channel address to CHADR (4000)x: (0000 0000 0000 0110)b
- Write the cutoff data to DATA (4002)x: (0000 0000 0000 0000)b.
Figure A-2 shows the VM8PF register map and defines the read/write function of each bit. Registers may
be accessed as words or as bytes.
ERROR HANDLING
Attempting to access the VM8PF board in other than A16 address space will cause a bus timeout.
Attempting long word access or unaligned transfers will cause the board to respond to the bus cycle with a
bus error (BERR).
Changing the channel address while BUSY is set would result in erroneous data during a data read
operation and would corrupt the settings of two or more channels during a data write operation. VM8PF
hardware prevents changing of the channel selection while BUSY. Writing to the Data Register while
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VM8PF
Programmable
Filter
8 Channel VME Module
BUSY is set is also inhibited in hardware. Neither event is flagged by the board, so it is important to use the
BUSY interlock before writing to either register.
Reading the Data Register while BUSY is set will yield erroneous data but will not impair board operation
or contaminate any filter settings. This event is not flagged, so it is important to use the BUSY interlock
before reading the Data Register.
It is not possible to write '0' to the BUSY bit from the VMEbus, so this is not an error. Attempting to write
'1' to the BUSY bit when it is already set is also not an error condition and therefore is not flagged.
POWER DISTRIBUTION AND GROUNDING
In an effort to minimize noise and channel-to-channel cross talk, the VM8PF uses individual linear voltage
regulators and separate supply filtering for each channel. The common analog power source is a pair of low
noise DC/DC converters, which are separately regulated and filtered. Each channel has its own ground and
power planes that connect to the common isolated supply in a "star" arrangement.
While all channels share a common low noise analog signal ground, they are galvanically isolated from the
VMEbus and chassis grounds. Thus, the VM8PF board can be ground referenced to external equipment
through the I/O cabling without causing ground loops.
Figure A-1
VM8PF Filter Programming Hardware Interface
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VM8PF
Programmable
Filter
8 Channel VME Module
Figure A-2
VM8PF Register Map
16
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e-mail: [email protected] • Web Address: http://www.freqdev.com
VM8PF
Programmable
Filter
8 Channel VME Module
Appendix B
VM8PF Specifications
(@ 25oC and rated Power Input)
Analog Input
1. Input Impedance
2. Input Range
3. Maximum Input
4. Common Mode Rejection
1 MΩ
+/-10V pk. linear
+/-15V
70 dB typ., 60 dB min. DC to 1 kHz
Analog Output
5. Impedance
6. Linear Operating Range
7. Channel-to-Channel Crosstalk
8. Maximum Current
9. Offset Voltage
10. Short Circuit Protection
1Ω typ., 10Ω max.
+/-10V pk.
-95 dB typ. DC to 100 kHz
+/-2 mA
+/-2mV typ., trimmable to zero
Short to Ground
Filter Characteristics
11. See 824 and 828 Series specifications
12. External 8-bit CMOS latches hold frequency data
Gain
13. Low-pass
High-pass
x1, +/-1%
x1, +/-2%
VMEbus
14. Interface
A16/D16, D08(EO) Slave only, VME Spec. Rev. C.1
Power Required
15. From VME Backplane
+5V, 3.5 A max.
Environmental
16. Operating
17. Storage
18. Humidity
0oC to +70oC
-25oC to +85oC
0-95% non-condensing
Mechanical
19. Card Size
20. No. of Input Channels
21. No. of Output Channels
22. Mating Connectors
23. Weight
VMEbus 6U single slot 9.17 x 6.3 inches, (233 x 160 mm)
8 Differential - DC coupled
8 Single Ended - DC coupled
25-pin "D", Quantity 3
3 lbs., (1.36 kg.)
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VM8PF
Programmable
Filter
8 Channel VME Module
Appendix C
VM8PF Ordering Guide
Available Low Pass Filter Options
D828L8B
D828L8E
D828L8EX
D828L8EY
D828L8L
D828L8D60
D828L8D80
D828L8D10
D824L8B
D824L8L
D824L8Y2
D824L8Y5
8-pole Butterworth
8-pole, 6-zero elliptic 1.77 (-80dB)
8-pole, 6-zero elliptic 1.56 (-80dB)
8-pole, 6-zero elliptic 2.00 (-100dB)
8-pole, Bessel
8-pole, constant delay (-60dB)
8-pole, constant delay (-80dB)
8-pole, constant delay (-100dB)
4-pole Butterworth
4-pole Bessel
4-pole Chebychev (0.2dB Ripple)
4-pole Chebychev (0.5dB Ripple)
Available High Pass Filter Options
D828H8B
D828H8E
D828H8EX
D828H8EY
D824H8B
D824H8Y2
D824H8Y5
8-pole Butterworth
8-pole, 6-zero elliptic 1.77 (-80dB)
8-pole, 6-zero elliptic 1.56 (-80dB)
8-pole, 6-zero elliptic 2.00 (-100dB)
4-pole Butterworth
4-pole Chebychev (0.2dB Ripple)
4-pole Chebychev (0.5dB Ripple)
Available Band Pass Filter Options
824BP
828BP
2-pole pair
4-pole pair
Available Band Reject Filter Options
828BR
4-pole pair
18
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VM8PF
Programmable
Filter
8 Channel VME Module
Ordering Information
For flexibility in many applications the Frequency Devices VM8PF VMEbus Filter board may be ordered
with two different filters on the same board. Channels 0 through 3 may be configured with one filter model
while channels 4 through 7 are configured with a different model.
VM8PF-D828H8E-2/D828L8E-6
|
|
Channels 0, 1, 2, and 3 ____________|
|
|
|___________ Channels 4, 5, 6, and 7
Note: See the D824, D828, 828BP, and 828BR Data Sheets for available models and tuning ranges.
We hope the information given here will be helpful. The information is based on data and our best knowledge, and we consider the information to be true and accurate. Please read all
statements, recommendations or suggestions herein in conjunction with our conditions of sale which apply to all goods supplied by us. We assume no responsibility for the use of these
statements, recommendations or suggestions, nor do we intend them as a recommendation for any use which would infringe any patent or copyright.
19
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e-mail: [email protected] • Web Address: http://www.freqdev.com