3170-PDP
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FLEX Platform
How Communication Takes Place and I/O Image Table Mapping
FLEX I/O™ PROFIBUS Adapter
Page 32 of 152
ProSoft Technology, Inc.
August 23, 2007
1794-OE4 Word/Bit Descriptions
Word Decimal
Bit
Definition
Read Word 1
Bits 00 to 03 Current outputs only – When set (1), the wire on the output is
broken or the load resistance is too high. Bit 00 corresponds to
channel 0, bit 01 corresponds to channel 2, and so on.
Bits 04 to 14 Not used – set to 0.
Bit
15
Power Up bit – included in series B modules only. This bit is 0 in
series A modules. This bit is set to 1 when all bits in the
configuration register are 0 (unconfigured state). The configuration
register can be cleared by either of the reset inputs, or by the user
writing all zeroes to it.
Write Word 1
Bits 00 to 14 Channel 0 analog data – 12-bit left justified two's complement
number; unused lower bits are zero; 4 to 20mA uses all 16 bits.
Bits 15
Channel 0 analog data sign bit.
Write Word 2
Bits 00 to 14 Channel 1 analog data – 12-bit left justified two's complement
number; unused lower bits are zero; 4 to 20mA uses all 16 bits.
Bits 15
Channel 1 analog data sign bit.
Write Word 3
Bits 00 to 14 Channel 2 analog data – 12-bit left justified two's complement
number; unused lower bits are zero; 4 to 20mA uses all 16 bits.
Bits 15
Channel 2 analog data sign bit.
Write Word 4
Bits 00 to 14 Channel 3 analog data – 12-bit left justified two's complement
number; unused lower bits are zero; 4 to 20mA uses all 16 bits.
Bits 15
Channel 3 analog data sign bit.
Write Word 5
Bits 00 to 03 Output Enable bits. Bit 00 corresponds to input 0, bit 01
corresponds to input 1, bit 02 corresponds to input 2, and bit 03
corresponds to input 3. These bits must be set to 1.
Bits 04 to 15 Not used – set to 0.
Write Word 6
Bits 00 to 03 Full range bits (F) for individual channels – Bit 00 corresponds to
output channel 0, bit 01 corresponds to output channel 1, and so
on. Refer to range selection above.
Bits 04 to 07 Not used – set to 0.
Bits 08 to 11 Configure select bits (C) for individual channels – Bit 08
corresponds to output channel 0, bit 09 corresponds to output
channel 1, and so on. Refer to range selection above.
Bits 12 to 15 Not used – set to 0.
Write Word 7
Bits 00 to 15 Not used – set to 0.
Write Word 8
Bits 00 to 15 Not used – set to 0.
Write Word 9
Bits 00 to 15 Not used – set to 0.
Write Word 10 Bits 00 to 15 Not used – set to 0.
Write Word 11 Bits 00 to 15 Not used – set to 0.
Write Word 12 Bits 00 to 15 Not used – set to 0.
Write Word 13 Bits 00 to 15 Not used – set to 0.
Write Word 14 Bits 00 to 15 Not used – set to 0.
