Panasonic Minas A4 Series - Page 289

287
[Supplement]
Supplement
Status Transition Chart
• RS232 Communication
Receiver
Transmitter
Ready for EOT
Block transmission
Ready for ACK/NAK
Reception of remained block
Ready for finish of receiving data
Ready for command byte counts
Idling = It waits for the reception of ENQ, and or it is dealing with reception.
Reception of EOT 
Size Command bytes+3
T2 stop
Enquiry for 
transmission, and
retry times are 
within setup
Transmission of
ENQT2 start
Enquiry for transmission, but
retry times are over.
Reset of retry times
Clear of transmission enquiry
T2 time out 
One count of retry times 
T2 stop Clear of 
transmission buffer
Size becomes 0 
T2 START
Reception of other than 
ACK orT2 time out
Count once of retry times
T2 stop
Clearance of transmission 
buffer
Reception of ACK
Reset of retry times
T2 stop
Clear of transmission 
enquiry
Transmission of 
one character
Size Command bytes–1
Reception of ENQ and 
at slave
Return ENQ to reception
buffer
(reception processing)
ENQ
Transmission 
of
EOT
T2 start

T2 time out
Transmission of NAK, 
T2 stop

Reception of command byte counts
Size command byte counts + 3
Sum command byte counts
T1 start, T2 stop
T1 time out
Transmission of NAK, 
T1 stop

Success of reception
(Check sum OK'ed when 
size becomes o.)
Transmission of ACK, 
T1 stop
Failure of reception.
(Check sum OK'ed when
size becomes o.)
Transmission of ACK, 
T1 stop
Reception of one character
Size Size –1
Sum Sum + received character
T1 start
Reception of 
one character
T1 start
T1 time out
Transmission 
of NAK, 
T1 stop