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11. Notes
11.1 Data Communication Delay
It will take certain time to synchronize when the frequency group setting is 2 frequency channel mode or 3
frequency channel mode.
11.1.1 Delay at the transmission side
(1) Delay due to the number of frequency channels in use
When the setting of the FDP03 is 2 frequency channel mode and/or 3 frequency mode, the FDP03
changes the data transmission frequency channel as every data re-transmission. It takes 7.6 ms to
re-transmit a data packet for packet generation, carrier sensing and waiting ACK time-out. Thus, the
data communication will be delay when the setting of the FDP03 is 2 frequency channel mode and/or 3
frequency mode.
(2) Delay due to carrier sensing
If the FDP03 detects radio wave that is same frequency channel as own use, the FDP03 switches the
carrier frequency channel to another. It is called "carrier sensing" and takes 7.6 ms. Thus, the data
communication will be delayed if other wireless systems such as WiFi in the same area.
11.1.2 Delay at the reception side
(1) Delay due to extension of reception-wait time
The FDP03 extends reception-wait time according to the frequency it has received. The extended
reception-wait time depends on the on the number of frequencies in the frequency group, which is "10+5
x (number of frequencies in the frequency group)2" ms. Since the FDP03 keeps the same frequency
during the extended reception-wait time, the extension of reception-wait time may cause a delay in
communication in an environment with much noise or jamming.
11.2 Reception of Same Packets
The FDP03 can store five packets of received data in the reception data buffer. However, when it receives
more than 5 packets, the FDP03 deletes the data packet from the oldest data one after the other. For example,
if the local FDP03 receives data packets from six remote FDP03s at the same time, one of the received data
packet is eliminated. Therefore, when the FDP03 receives a data packet that is same as the eliminated one,
the FDP03 cannot realize the duplication of the data packet and output the data to the host.
when the FDP03 is used in below listed condition.
(1) More than seven or more FDP03s operate at the same time in the system.
(2) Data re-transmission is frequent.
(3) The data packets having the same packet size are transmitted.
Even if the local FDP03 cannot receive the ACK signal of a packet from the remote FDP03, the remote FDP03
may success to received the packet.
11.3 Timing of Command Input
Do NOT execute next command before the sender FDP03 receives P0 response. If the setting is "Disabling
response" and no P0 response is sent to the sender FDP03, please wait expected P0 response time before
executing next command. If next command is executed before P0 response, command error is occurred and
the system might have unexpected movement.
When "Disabling response" is defined, the command should be executed after waiting the specific time that is
defined by REG15.
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Ver.1.0
It will happen
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