Xycom XVME 590, Руководство пользователя

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XVME-500/590 Manual
February, 1988
2.6 ANALOG-TO-DIGITAL (A/D) CONVERSION OPTIONS
2.6.1 Input Conversion Format Jumpers
(Jl, J4)
This jumper option is used to configure A/D conversion circuitry to convert analog
information to one of three formats:
straight binary (unipolar); off set binary
(bipolar); or two’s complement binary (bipolar).
Use of this option is dependent upon the data format required by the input control
program employed by the user.
This option is inclusive to all input channels and
cannot be utilized on an individual channel basis (see Section 3.3.4.1).
The digital-data format at the A/D converters may be changed (via jumpers) to
accommodate several types of data encoding.
Table 2-5 shows which jumpers
control the data formats for the two different voltage modes.
Table 2-5. Input Conversion Format Jumpers
Digital Data Conversion Jumpers Input
Format ( All Inputs) Installed Mode
.
Analog to Straight Binary JlA, J4A
Analog to Offset Binary JlA, J4A
Analog to Two’s Complement JlB, J4B
Unipolar
Bipolar
Bipolar
2.6.2 Differential, Pseudo-Differential/Single-Ended Input Option Jumpers
(Analog Multiplexers) (J21, J25)
The XVME-500/590 can be configured to provide any one of three types of channel
modes in set numbers (see Table 2-6 for input selection jumper options) They are:
1) 16 single-ended (SE) input channels, or
2) 8 differential (DI) input channels, or
3)
16 pseudo-differential (PDI) input channels (allows module to simulate
advantages of true differential with some degradation)
The three modes are mutually exclusive so the module will only accept all SE, or all
DI, or all PDI inputs. It will not accept combinations of the three.
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