Submittal Sheet

7800 SERIES S7800A2142 KEYBOARD DISPLAY MODULE
32-00110—05 56
Device Address and Baud Rate
Assign each device in the system a unique address by setting
the MODBUS ADDRESS (see page 28). Only RTU
communications with 1 Start Bit, 8 Data Bits, 1 Stop Bit and
no, odd, or even parity is supported.
NOTE: Assign a device address number from 01 to 255.
00 is not an acceptable address number and will
not work.
NOTE: In Table 16: Line 1 and Line 2 refer to the two
lines of text on the S7800 Keyboard Display Mod-
ule. In Table 20: The String Code column refer-
ences Table 21, String Codes. In Table 16: The
Burner Control State Bits column references
Table 19, Burner Control State Bits.
Table 16. ModBus™ Register Assignments.
Address
(hex)
Register
(dec) Parameter Name
Read/
Write Format Notes
0000 40001
Burner Control (BC) Fault
Code
R U16 See Table 22. Non-zero value = Lockout number.
0001 40002 BC Fault String Code R U16 See Table 21. Lockout text.
0002 40003 BC Sequence State R U16 See Table 20 (valid only if Fault code = 0).
0003 40004 BC State String Code (line 1) R U16 See Table 21. Simulates Line 1 of S7800.
0004 40005 BC State String Code (line 2) R U16 See Table 21. Simulates Line 2 of S7800.
0005 40006 BC Sequence time R U16 0-4095 Seconds.
0006 40007 BC Total cycles R U32 Max value is 0xFFFFFFFF.
0008 40009 BC Total hours R U32 Max value is 0xFFFFFFFF.
000A 40011 BC Flame 1 signal strength R U16 0 to 255 represents 0.0 to 25.5 volts. Not clipped to
5.0V like S7800.
000B 40012 BC Flame 2 signal strength R U16 0 to 4095. N/A for 7800 SERIES.
000C 40013 BC State Bits R U16 See Table 20.
000D 40014 S7830 First Out Code R U16 Not supported from S7800.
000E 40015 S7830 State Bits R U32
0010-
0019
40017-
40026
BC Fault history record 1 R Newest fault record. See Table 23.
001A-
0023
40027-
40036
BC Fault history record 2 R Second newest fault record. See Table 23.
0024-
002D
40037-
40046
BC Fault history record 3 R Third newest fault record. See Table 23.
002E-
0037
40047-
40056
BC Fault history record 4 R Fourth newest fault record. See Table 23.
0038-
0041
40057-
40066
BC Fault history record 5 R Fifth newest fault record. See Table 23.
0042-
004B
40067-
40076
BC Fault history record 6 R Oldest fault record. See Table 23.
004C 40077 BC Flame Failure Response
Time
R U16 Tenths of Seconds.
004D 40078 BC Manufacturing code R U32
004F 40080 BC Type Code R U16 See Table 18.
0050 40081 S7800M/BC Software
version
RU32
0052 40083 EA Software version R U32 Does not apply.
0054 40085 BC Remote Command
status.
R U16 Bit 0: Autonomous.
Bit 1: Remote commanded off.
Bit 2: Remote commanded High fire.
Bit 3: Remote commanded low fire.
Bit 4: Remote reset has/will be sent to BC.
a
Bits 5-14: Unused.
Bit 15: Copied after the most recent write to the
burner control command (40128 bit 15).