Omron V600 Series Operation Manual page 26

Data Carrier Memory Map
3-2-4 Data Carrier Usage Level Check Function
SRAM DC with Battery
Battery Check
1, 2, 3...
24
The following is an example of the conditions of addresses 0006 to 07FF to be
write protected.
Address Upper bits
0002
1 0
8
0003 0 0
0
0004 0 0
0
0005
1 1
F
When the addresses are not write protected, the conditions of the addresses are
as follows:
Address Upper bits
0002 0 0
0
0003 0 0
0
0004
0 0
0
0005 0 0
0
The Data Carrier's usage level check function varies with the Data Carrier's
memory (SRAM or EEPROM). With the SRAM DC, usage level is obtained from
the battery check function. With the EEPROM DC, the usage level is obtained
from the number of rewriting operations (100,000 max.).
Data Carrier battery checks are not performed automatically, only when the con-
tents of the production date area (addresses 0000 and 0001) are read. When a
battery check is performed, a small current is passed through the DC's internal
circuitry. Too much power would be consumed if a battery check was performed
automatically every time DC memory was accessed.
Use one of the following commands to read the contents of the production date
area and check the battery's production date and current status. (The s at the
end of each command means carriage return.)
1. Read command: RD H/A 1/2 0000 02*s
2. Auto Read command: AR H/A 1/2 0000 02*s
3. Polling Auto Read command: PR H/A 1/2 0000 02*s
If the end code of the response is 00, the battery is operating normally. If the end
code is 7B, the battery is low. The following are responses to Read and Auto
Read commands sent to a DC with a good battery:
RD 0 0 0 9 9 5 *
AR 0 0 0 9 9 5 *
Normal completion code
0 0 0
0
0 0 0
6
0 0 0
7
1 1 1
F
0 0 0
0
0 0 0
0
0 0 0
0
0 0 0
0
Read data
Production date: Sept., 1995
Section 3-2
Lower bits
0 0 0
1 1 0
1 1 1
1 1 1
Lower bits
0 0 0
0 0 0
0 0 0
0 0 0