Справочник Пользователя для Agrident Corporation ASR700
05.07.2007
Page 46 of 56
ASR700 Reader Operation
6.
Clock synchronisation of ASR 700 readers
When two or more antenna fields are overlapping there might be some interferences with FDX
transponders. This is due to the very small differences of the frequency generated by the oscil-
lator (clock) of the readers.
transponders. This is due to the very small differences of the frequency generated by the oscil-
lator (clock) of the readers.
To prevent this interference it is possible to synchronize the readers, this means that the clock
generated by the oscillator of one reader is used for the additional readers. The reader, which
generates the oscillator clock, is called clock master and the readers that receive the oscillator
clock are called clock slave.
generated by the oscillator of one reader is used for the additional readers. The reader, which
generates the oscillator clock, is called clock master and the readers that receive the oscillator
clock are called clock slave.
6.1 Installation
• The total length of the cables for the synchronization should not exceed 4 meters.
• Recommended types of cable for the connection are shielded twisted pair or coaxial cable
• Recommended types of cable for the connection are shielded twisted pair or coaxial cable
RG58 or coaxial cable RG174.
A connection between –UB (ST7 pin2) and G (e.g. ST7 pin5 or ST7 pin7) influences and may
improve the reading range.
If the Agrident power supply is used, it’s possible to connect earth and ground of the power sup-
ply (fuse, F2), which also influences the reading range of the devices.
6.2 Setting at the ASR700
Clock master Jumper 3 open, that means to use the reader’s own oscillator for generating the
frequency.
Clock slave Jumper 3 closed, that means use the clock coming in at ST7 pin 9 (Clock In). If
the connection (from ST7 pin 8 Clock Out of the master) is not made, the slave will not work.
frequency.
Clock slave Jumper 3 closed, that means use the clock coming in at ST7 pin 9 (Clock In). If
the connection (from ST7 pin 8 Clock Out of the master) is not made, the slave will not work.
Figure 15: Connection diagram ASR700 as master