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CHAPTER 7 PROCESSING TIME
7
7.4 Dedicated Instruction Transmission Delay Time
7.4.1 Link dedicated instruction transmission delay time
(b) Transmission delay time for the READ/WRITE instruction
*1 For the scan time delay due to tracking transfer, refer to the following.
QnPRHCPU User's Manual (Redundant System)
Sending station Transmission delay time of when the receiving station is a non-redundant system [ms]
Non-redundant system TD1 = {(ST + T) × 2 + LS × 11 + (SR + R)} × m
Redundant system TD1 + TsT × 2 × m
Sending station
Transmission delay time of when the receiving station is a redundant system and
transmission does not pass through a tracking cable [ms]
Redundant system (control system CPU) Redundant system (standby system CPU)
Non-redundant system TD2 = {(ST + T) × 2 + LS × 11 + (SR + R + TsR)} × m TD3 = {(ST + T) × 2 + LS × 11 + TsR} × m
Redundant system TD2 + TsT × 2 × m TD3 + TsT × 2 × m
Sending station
Transmission delay time of when the receiving station is a redundant system and
transmission passes through a tracking cable [ms]
Access to control system CPU through standby
system
Access to standby system CPU through
control system
Non-redundant system TD4 = {(ST + T) × 2 + LS × 11 + (SR + R + TsR) + 6} × m TD5 = {(ST + T) × 2 + LS × 11 + TsR + 6} × m
Redundant system TD4 + TsT × 2 × m TD5 + TsT × 2 × m
TD1 to TD5: Transmission delay time for the READ/WRITE instruction
ST: Sequence scan time on sending side (except link refresh time and scan time delay due to tracking
transfer)
SR: Sequence scan time on receiving side (except link refresh time and scan time delay due to tracking
transfer)
T: Link refresh time on sending side (Total of the number of mounted network modules)
R: Link refresh time on receiving side (Total of the number of mounted network modules)
m: Number of fragmented transmissions = (Read or write data length) / 960 (Rounded up to the nearest
integer)
TsT: Scan time delay due to tracking transfer on the sending side
*1
TsR: Scan time delay due to tracking transfer on the receiving side
*1
LS: Link scan time