User's Manual

RF300 transponder
7.1 Memory configuration of the RF300 transponders
SIMATIC RF300
System Manual, 07/2016, C79000-G8976-C345-0x
209
EEPROM area
The memory configuration of an RF300 transponder always comprises an EEPROM that has
20 bytes for user data (read/write) and a 4-byte unique serial number (UID, read only). For
reasons of standardization, the UID is transferred as an 8 byte value through a read
command to address FFF0 with a length of 8. The unused 4 high bytes are filled with zeros.
Note
Write speed
The EEPROM user memory (address FF00
-FF13, or FF80-FF90) requires significantly more
time for writing (approx. 11 ms/byte) than the high
-speed FRAM memory. For time-critical
applications with write functions, it is advisable to use FRAM transpond
ers (e.g. RF330T,
RF340T, RF350T, RF360T, RF370T, RF380T).
FRAM area
Depending on the tag type, high-speed FRAM memory is available. (8 KB, 32 KB, 64 KB).
This area does not exist for the RF320T.
In the case of RF3xxT transponders with FRAM memory, the data carrier initialization
command (INIT) is only effective on this memory area but not on the EEPROM area (FF00-
FF13).
OTP area
The EEPROM memory area (address FF00-FF13) can also be used as a so-called "OTP"
memory (One Time Programmable). The 5 block addresses FF80, FF84, FF88, FF8C and
FF90 are used for this purpose. A write command to this block address with a valid length (4,
8, 12, 16, 20 depending on the block address) protects the written data from subsequent
overwriting.
Note
Seamless use of the OTP area
When the OTP area is used, it must be ensured that the blocks are used starting from Block
0 consecutively.
Examples:
•
3 blocks (with write command), Block 0, 1, 2 (FF80, length = 12): valid
•
2 blocks (consecutive), Block 0 (FF80, length =4), Block 1 (FF84, length = 4): valid
•
2 blocks (consecutive), Block 0 (FF80, length =4), Block 2 (FF88, length = 4): Invalid
•
1 Block, Block 4 (FF90, length = 4): Invalid