Datakom DPR-350 Series, Руководство пользователя

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DPR-350 User Manual Ver_01 Firmware V-1.0
K91D01-EN - 65 -
Follow the method shown below for CRC calculation,
1) A 16-bit variable named CRC with every bit set to 1 is initialized.
2) The result of the Boolean logic operation XOR of the bottom byte of CRC and the first byte of the
message (Function Code) is appended to CRC.
3) The least significant bit (LSB) of CRC has been defined. CRC is shifted right by 1 bit. Most
significant bit (MSB) of the CRC is set to 0.
4) If the LSB of the CRC is 1, CRC
is XOR’d by A001h. The result is appended to CRC.
5) Steps 3 and 4 are repeated until 8 bits have been shifted.
6) Steps 2, 3, 4, 5 are repeated for the remaining 8 bits.
7) Once the process is complete for the entire data, the intermediate CRC value becomes final.
8) The calculated CRC is appended to the message packet starting with the bottom byte. The final
CRC value that must be calculated by the algorithm is shown below.
01 03 00 20 00 10 45 CC
01 06 00 40 00 10 89 D2
The unit has 15000 records of 64 bytes each in its 1MB memory. In order to read records, the record
number (0 .. 14999) must be typed into the address
“16389”. Then, the relevant record can be read
starting from the address
“4096”.
REGISTER
ADDRESS VARIABLE DESCRIPTION SIZE
(BIT)
R/W
TYPE
X
+0
+1
Date
– Time
32-bit date and time information
Bits 0-4: second/2 (0-29)
Bits 5-10: minute (0-59)
Bits 11-15: hour (0-23)
Bits 16-20: day (1-31)
Bits 21-24: month (1-12) Bit
25-31: year-2000
(0-127=2000-2127)
32 R-O bitmap
+2_BOT Type Register Type 8 BIT R-O unsigned byte -
+2_TOP Argument Register Info 8 BIT R-O unsigned byte -
+3_BOT
Input -
Output
Status
Bits 0-4: digital input status
Bits 5-7: digital output status
8 BIT R-O bitmap 100
+3_TOP - Reserved
+4 V1
Voltage / Voltage Transformer
Ratio
16 BIT R-O
Unsigned
word
x1
+5 V2
+6 V3
+7
U12
+8 U23
+9
U31
22.5. CRC CALCULATION
22.6. INTERNAL RECORD STORAGE STRUCTURE