Honeywell S7800A - Page 35

7800 SERIES S7800A KEYBOARD DISPLAY MODULE
35 65-009 0-6
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Table 16. ModBus™ Register Assignments. (Continued)
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A
dd
r
ess
(hex)
Registe
r
( d ec)
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Parameter Name
Read
/
Write
Format Notes
0066 40103 Post-Purge time R U16 Seconds
0067 40104 Valve P
r
oving Mode R U16 0 = Valve P
r
oving is not enabled
1 = Enabled before Run
2 = Enabled after Run
3 = Enabled before and after Run
4 = Enabled split half before and half after Run
0068 40105 Valve P
r
oving options R U16 1 = Uncommissioned
2 = Commissioned
0069 40106 Valve P
r
oving time R U16 Seconds
0066-
007E
40103-
40127
Unused
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007F 40128 BC Remote Command R/W U16 Only one bit in the LSByte must be set,
w
ith the exception of bit 15:
Bit 0 =Revert to autonomous operation.
Bit 1 = Don't fire, remain off.
Bit 2 = Go to Hi Fire during Run.
Bit 3 = Go to Lo Fire during Run.
Bit 4 = Remote reset.
a
Bits 5-7 must be 0.
Bits 8-14 are ignored.
Bit 15: Copied to the control status register. The remote
control status register can be used to verify operation of the
command.
Bits 1-3 must be refreshed at least every 120 seconds, but
not more than once a second, for the burner control to
remain in the commanded state.
01B7-
01B8
40440-
40441
Unused
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U32
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01BA 40443 Device Da
t
a Ready
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U16 Device da
t
a was properl
y
r
eceived b
y
S7800.
Bit(s) Device
0 RM78XX
3 EC78XX
4-15 Unused
01BB 40444 S7800 Device Compatibility
with Current Software
Revision
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S7800 Software Revision
Compatibility with Legacy
Software Revisions.
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U16 Device is compatible
w
ith the S7800 version.
Bit
Device
0 RM78XX
3 EC78XX
4-7 Unused
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Used for indication of S7800 revision compatibility.
Bit(s) Compatible with:
8 Series 2
9-15 Future
NOTE: "Device Data Ready" and "S7800 Compatibility" bits can be used to quickly check device availability and compatibility
then read/write registers of only these devices.
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Response Message Format for Function Code 17.
This format is device specific and is only available for the 7800
SERIES burner control. See Table 17.
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Table 17. Response Message Format for function code 17 (11h), (26 bytes).
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Sla ve
Address
Function
Code
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Byte Count Slave lD
a
Run lndi cator
Stat
u s
b
Device
Descr
iption
c
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N/A
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CRC CRC
Byte 0 1 2 3 4 5-15 16-23 24 25
a
Slave ID: Always 0x78 when using RM78xx or EC78xx Relay Modules(1 byte) (byte 3).
b
Run Indicator Status: Always FF=ON (one byte) (byte 4).
c
Device Description: 16 Character ASCII OS number for the Burner Control (11 bytes) (bytes 5-15).