User's Manual

Ver.1.0
2
At that time, the receiver FDP03 responds an acknowledgement “ACK” signal to the sender FDP03 for
notifying data packet receiving if "Enabling destination address check at reception" function of the REG18
register is turned on. On the other hand, when the function of "Disabling destination address check at
reception" in the REG18 register is turned on, the receiver FDP03 does not return ACK signal to the sender
FDP03 and also it receives all packet data regardless of the destination address of the packet.
Packet data transmission from the sender to the receiver is finished when the sender FDP03 receives ACK
signal. At that time, the sender FDP03 outputs P0 response if "Enabling response" functions of the REG13
register is turned on. When the sender FDP03 cannot receive ACK signal within the time-out limit, the
sender FDP03 transmits the same packet data to the destination receiver through the air if the re-try frequency
is registered. (The re-try frequency can be set by REG11 register
When the receiver FDP03 receives the same packet several times, it ignores from the second data downward.
Also, the receiver FDP03 sends ACK signal to the sender FDP03 if the function of "Enabling destination
address check at reception" of REG18 register is turned on.
If the sender FDP03 cannot receive ACK signal even it sent packet data defined times by the REG11 register,
it outputs N1 response to the host device via the serial port when "Enabling response" function of REG13
register is turned on. No response signal is sent if the function of "Disabling response" in REG13 is turned
on
The figure below shows an operation example of data packet communication between a sender FDP03 that the
"Enabling response" and "Returning P0 and P1 responses" functions of REG13 register are turned on and a
receiver FDP03 that "Enabling destination address check at reception" function of REG18 register is turned on.
At the figure, data communication is completed by “ACK” signal retry.
① The Host 1 inputs data to the sender FDP03 via the serial port.
② The sender FDP03 recognizes the data packet configuration as valid and returns a P1 response to the Host
1 (Data is accepted).
③ The sender FDP03 transmits the data packet to the destination, which is the receiver FDP03, by wireless
transmission.
④ The receiver FDP03 receives the packet and outputs the received data packet to the Host 2 via the serial
port.
⑤ The receiver FDP03 returns ACK to the sender FDP03 by wireless transmission.
⑥ Time-out is occurred at the sender FDP03 because it cannot receive the receiver's ACK signal at the first
transmission. The sender FDP03 re-sends the data packet transmission.
⑦ The receiver FDP03 receives the same data packet as the previously received one. Thus, the receiver
FDP03 ignores the received data but returns ACK signal to the sender FDP03.
⑧ The sender FDP03 receives the ACK signal and outputs a P0 response to the Host 1.
Data input
P1 response
Wireless transmission
Return of ACK
Time-out
Data output
P0 response
Host 1 FDP02 (sender) FDP02 (receiver) Host 2
①
②
③
⑤
④
⑥
⑦
⑧
⑦
The data same as previously
received data is received and
discarded.
Return of ACK
Wireless transmission