Edwards STP-iS2207 Series - Page 100

STP-iS2207 Series Turbomolecular Pump
MT-89E-001-C
Page 90
5
SERIAL COMMUNICATION PROTOCOL
This procedure is not necessary
if total block N = 1.
*1 When using RS485 to communicate,
switch the PC side from sending state to
receiving state within 5 sec.
*2 When using RS485 multipoint connection,
also an address is incorrect.
Send
c
ommand (N block
s
)
Block number: k = 1
k = k + 1
Yes
No (Timeout 2sec)
Command sending success
Send block (k)
Retry?
Command sending failu
re
No
*2
Yes
No
Yes
No
Yes
Block check:
k = N?
*1
Acknowledge
received?
ACK received?
Figure 48 - Example of command sending process
This procedure is not necessary if N = 1.
*1 When using RS485 multipoint connection,
also an address is incorrect.
*2 When using RS485 to communicate, send after 1
msec or more progress from block data received.
*3 When using RS485 multipoint connection,
send with address data.
Receive
answer (N blocks)
Correct
LRC
k = k + 1
ETX
received?
Block (k)
received
?
Yes
Answer receiving success
Send ACK
Retry?
A
nswer receiving failure
Send NAK
Block number:
k = 1
No
*1
No
Yes
No
Yes
*
2
, *
3
No (Timeout 2sec)
Figure 49 - Example of answer receiving process