Application and Installation Guide EMCP 4 SCADA Data Links
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Response: 0x 01 10 02 BB 00 08 xx xx
0x 02 BB = Write Access Password
0x 00 08 = register count (8)
Again, repeat Step 1 to verify the current security level.
Response: 0x 01 03 02 00 00 xx xx
This verifies that the SCADA password worked, and did indeed give access to level 0 security. Notice that
the level did not increase to 1 or 2 because a level 1 password is set. If the level 1 password is entered,
access level 2 would be granted because there is no level 2 password set.
NOTE ON SCADA PASSWORDS
Note that the SCADA password is stored as a numeric value. The password is right-justified in the field
shown on the EMCP 4 display, and left-justified when set/written over SCADA. So for example, if the
password is set on the EMCP 4 to be 00000020, when the security access is requested via SCADA, the
value sent must be 20______ (20 with six spaces after it), Just as with any number, leading zeros get
dropped, and trailing zeros are kept (so 01 is stored as 1, but 10 is stored as 10).
Also, the first space terminates the string, so an entry of 12_3 (space between the 2 and the 3) will return
an exception because only spaces (or nulls, after the first 8 bytes) are accepted after the first space.
7.5 REAL TIME CLOCK
The 1985 year offset implies that 0x14 in byte 5 translates to 20 years past 1985, or year 2005. The day
offset implies that 0x1F (31) in byte 4 translates to the 8
th
day of the month (and the third quarter of the
day – noon to 6pm). One month offset implies that 0x07 in byte 3 translates to the seventh month, July.
Zero hour offset implies that 0x00 in byte 2 translates to 12:00 midnight, and with the 24-hour format,
0x0D translates to 13:00 or 1:00 pm. Zero minute offset implies that 0x05 in byte 1 translates to 5 minutes
past the hour (i.e. 12:05pm). Zero second offset implies that 0x4D (77) in byte 0 translates to 19 and a
quarter seconds past the minute (i.e. 12:05:19 pm).
Therefore, 0x 4D05 0D07 1F14 is 1:05:19pm on July 8, 2005.
7.6 READING ASCII DATA
Control Serial Number: 0x04FC (1276) - 6 registers (12 bytes) long - read
Reads the serial number of the EMCP 4. This is the number that is label printed on the back cover of the
control panel. For example, say the serial number is 3489B016TX, as shown in Figure Figure 7-4
below.F
IGURE 7-4: SAMPLE SERIAL NUMBER FOR EMCP 4 GSC
Byte 0: Character count
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