Datakom DKM-409 PRO AT, Руководство пользователя

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DKM-409 Pro AT User Manual Rev_02 Firmware V-2.5
K91D01-EN - 55 -
A method to create CRC is explained as follows,
1) Find one 16-bit free register and set all its bits to 1, which will be called as CRC.
2) Perform Exclusive OR operation between Lower byte of CRC, and First byte of the message
(function code). Write the result at CRC register.
3) Identify LSB of CRC, shift CRC register to 1 bit right. Modify MSB as 0.
4) Perform Exclusive OR operation between CRC and A001h, if LSB is 1.
5) Repeat 3. And 4. steps until 8 bit is shifted.
6) Repeat 2. 3. 4. 5. Steps for next 8 bit.
7) Remained value of CRC register is called CRC.
8) Add CRC to the message so that lower byte is sent first. Algorithm should return correct CRC for
messages below.
01 03 00 20 00 10 45 CC
01 06 00 40 00 10 89 D2
The unit has 1 MB internal record memory, consisting of 15000 blocks of 64 bytes.
In order to read the record memory, record
number (0…14999) should be written at address “16389”. Then
the related record can be read from address
“4096”.
REGISTER
ADDRES
VARIABLE DESCRIPTION LENGHT R/W TYPE X
+0
+1
Date-Time
32 bit date-time information
Bit_0..4: second/2 (0-29)
Bit_5..10: minute (0-59)
Bit_11..15: hour (0-23)
Bit_16..20: day (1-31)
Bit_21..24: month (1-12)
Bit_25..31: year-2000
(0..127=2000..2127)
32 BIT R-O bitmap
+2_LOW Type Log Type 8 BIT R-O unsigned byte -
+2_HIGH Argument Log Additional Info 8 BIT R-O unsigned byte -
+3_LOW
Input-
Output
Status
Bit_0..4: digital input statuses
Bit_5..7: digital output statuses
8 BIT R-O bitmap 100
+3_HIGH - Not Used
+4 V1
Voltage/Voltage transformer ratio
16 BIT R-O
Unsigned
word
x1
+5 V2
+6 V3
+7
U12
+8 U23
+9
U31
21.5. CRC CALCULATION
21.6. INTERNAL RECORD MEMORY STRUCTURE