KROHNE Summit 8800 Vol 3 - Manual (Page 171)

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08/2013 - MA SUMMIT 8800 Vol3 R02 en
SUMMIT 8800 APPENDIX3: MODBUS COMMIUNICATION PROTOCOL 12
12. APPENDIX 3: MODBUS COMMUNICATION PROTOCOL
Modbus commands 01, 02, 03, and 04 are supported for data reads and Modbus commands 05
and 10 are supported for Modbus writes.
The highest accuracy of numbers is achieved using double precision IEEE numbers to 64 bit
resolution. All numbers can be selected as types other than their default.
Variable address types
Any address in the range 0H to FFFFH or 0D to 65535D ID name of variable from data tree
Note. Read /write is only applicable to items with write access (red ID)
Record
Log record number zero (0) being the most recent log record.
12 .1 Number formats
Type Bits Range Description
Unsigned char 8 0..255 Character or boolean
Unsigned short
integer
16 0..65535 16 bit short integer format
Unsigned long integer 32 0.. 4294967295 32 bit long Integer format
Char 8 -128..127 8 bit character
Short integer 16 32768..32767 16 bit short integer
Long integer 32 2147483648 32 bit long integer
Float 32 -3.4E+38..3.4e+38 7 decimals, Single precision IEEE floating
point
Double 64 -1.7E+308..1.7E+308 16 decimals, Double precision IEEE floating
point
Time 64 SSMMHHWDDDmmYYmS
Time format:
Description Valid range
SS Seconds 0 to 59
MM Minutes 0 to 59
HH Hours 0 to 23 (0=midnight)
WD Week day 1 to 7 (1=Sunday)
DD Day 1 to 31
mm Month 1 to 12
YY Years 0 to 99 (assumed to be 20xx)
mS Milliseconds
00
zero
25 250 mS
50 500 mS
75 750 mS
255 Invalid clock (RTC device error)