Micromod Micro-DCI: 53IT5100B Micro-DCI 4-Channel Indicator Totalizer User Manual
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53IT5100B Indicator/Totalizer
INSTRUCTION MANUAL
Calculating Data Addresses
If communications software must be generated to accommodate unique Datalink applications requirements,
then the instrument memory address scheme must be known for proper data bit (e.g., L data type) and data
byte (e.g., B, C, H, and A data types) memory location determination.
NOTE: Numbers used in this section that are expressed in hexadecimal notation (base 16) are
identified with an H after the number.
This memory address scheme applies only if a 6 is in memory address location 8002H. Memoryaddress
location 8002H must be read and if it contains a 6, then the address scheme that is described in Table B-3
should be applied for this instrument.
Table B-3. Instrument Memory Address Scheme
Data
Type
Base
Memory
Address
Byte
Size
Data Format
Address Calculation Algorithm
B
200H
1
Represents a positive integer with
values from 0 to 255.
Address = B Base + (B Number)
= 200H + (B Number)
Address example: B012 location =
200H + 12D = 200H + CH = 20CH
L
500H
1 Bit A single binary bit with a logical
value of 0 or 1. L datapoints are
packed 8 to a byte.
Address = L Base + (L Number/8)
= 500H + (L Number/8)
Remainder = bit position in byte
Address example: L014 location =
500H + 14/8 = 501H, bit 6 (remainder).
C
600H
3
Represents floating point values that
have a resolution of one part in
32,768 (15 bits) and a dynamic
range of ± 1038 . The first two bytes
represent a 2’s complement notation
in fractional form (2-n ) whose
absolute value is between 0.5 and
0.9999. The third byte is the power
of 2 in 2’s complement notation.
Floating point example: 64H 00H
07H = 100D (Decimal) 64H = 0110
0100, fractional binary weights left to
right are 0 = 2’s complement
positive, 1 = 2-1 = 1/2 = 0.5, 1 = 2-2
= 1/4 = 0.25, 0=0, 0=0, 1 = 2-5 =
1/32 = 0.03125, 0=0, and 0=0. 64H =
0.5+0.25+0.03125 = 0.78125.07H =
128D. 128D X 0.78125D = 100.
Address = C Base + (3 X C Number)
= 600H + (3 X C Number)
Address example: C011 location
600H + (3 X 11) = 600H + 33D
= 600H + 21H = 621H.
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