Rev. 5.00, 09/03, page 426 of 760
13.4
Usage Notes
13.4.1
Register Writing during RTC Count
The following RTC registers cannot be written to during an RTC count (while bit 0 = 1 in RCR2).
RSECCNT, RMINCNT, RHRCNT, RDAYCNT, RWKCNT, RMONCNT, RYRCNT
The RTC count must be halted before writing to any of the above registers.
13.4.2
Use of Realtime Clock (RTC) Periodic Interrupts
The method of using the periodic interrupt function is shown in figure 13.6.
A periodic interrupt can be generated periodically at the interval set by the periodic interrupt
enable flag (PES) in RTC control register 2 (RCR2). When the time set by the periodic interrupt
enable flag (PES) has elapsed, the periodic interrupt flag (PEF) is set to 1.
The periodic interrupt flag (PEF) is cleared to 0 upon periodic interrupt generation when the
periodic interrupt enable flag (PES) is set. Periodic interrupt generation can be confirmed by
reading this bit, but normally the interrupt function is used.
Set PES, and clear PEF to 0,
in RCR2
Clear PEF to 0
Set PES, clear PEF
Elapse of time set by PES
Clear PEF
Figure 13.6 Using Periodic Interrupt Function
13.4.3
Precautions when Using RTC Module Standby
Before switching the RTC to module standby, access at least one among the registers RTC, SCI,
and TMU.
Summary of Contents for SH7709S
Page 2: ......
Page 44: ...Rev 5 00 09 03 page xliv of xliv ...
Page 62: ...Rev 5 00 09 03 page 18 of 760 ...
Page 128: ...Rev 5 00 09 03 page 84 of 760 ...
Page 146: ...Rev 5 00 09 03 page 102 of 760 ...
Page 224: ...Rev 5 00 09 03 page 180 of 760 ...
Page 246: ...Rev 5 00 09 03 page 202 of 760 ...
Page 266: ...Rev 5 00 09 03 page 222 of 760 ...
Page 370: ...Rev 5 00 09 03 page 326 of 760 ...
Page 432: ...Rev 5 00 09 03 page 388 of 760 ...
Page 532: ...Rev 5 00 09 03 page 488 of 760 ...
Page 598: ...Rev 5 00 09 03 page 554 of 760 ...
Page 630: ...Rev 5 00 09 03 page 586 of 760 ...
Page 656: ...Rev 5 00 09 03 page 612 of 760 ...
Page 684: ...Rev 5 00 09 03 page 640 of 760 ...
Page 700: ...Rev 5 00 09 03 page 656 of 760 ...
Page 758: ...Rev 5 00 09 03 page 714 of 760 ...
Page 807: ...SH7709S Group Hardware Manual REJ09B0081 0500O ADE 602 250C ...