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CHAPTER5 MEMORIES AND FILES USED FOR CPU MODULE
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5.1  Memories Used for CPU Module
5.1.3  Program cache memory
(2) Writing a program
When writing data from GX Developer, programs and parameters are written to the program cache memory in the 
CPU module. After the completion of the writing, the data are transferred to the program memory.
Figure 5.6 provides the flow of writing a program.
(3) Transferring data to the program memory by GX Developer
Data can also be batch-transferred from the program cache memory to the program memory by selecting [Online] 
 [Program memory batch transfer] in GX Developer. 
Figure 5.4 provides the transfer time required when data are batch-transferred to the program memory while the 
CPU module is in the RUN status.
Ts: scan time (s)
Figure 5.6 Flow of writing a program
Table5.4 Transfer time of program memory batch-transfer
CPU module Transfer time
Q00UJCPU, Q00UCPU, Q01UCPU, Q02UCPU
Ts 320 + 4.8 (s)
Q03UDCPU, Q04UDHCPU, Q06UDHCPU, Q03UDECPU, 
Q04UDEHCPU, Q06UDEHCPU
Ts 260 + 4.7 (s)
Q10UDHCPU, Q10UDEHCPU
Ts 439 + 6.2 (s)
Q13UDHCPU, Q13UDEHCPU
Ts 600 + 8.0 (s)
Q20UDHCPU, Q20UDEHCPU
Ts 839 + 11.4 (s)
Q26UDHCPU, Q26UDEHCPU
Ts 1100 + 15.0 (s)
<Drive 3>
Standard 
RAM 
(SRAM)
<Drive 4>
<Drive 0>
Program 
memory 
(Flash ROM)
Program 
cache 
memory 
(SRAM)
Universal model QCPU
GX Developer
1) Data are written to the program 
cache memory once.
2) After data are written to the program 
cache memory, the data are automatically  
transferred to the program memory.
Multiple 
CPU auto 
refresh area
Standard 
ROM 
(Flash ROM)