HD6417320 RENESAS [Renesas Technology Corp], HD6417320 Datasheet - Page 637

• Manufacturer Part Number: HD6417320
• Description: Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7700 Series
• Manufacturer: RENESAS [Renesas Technology Corp]

17.3.16 RTC Control Register 1 (RCR1)
RCR1 is a register that affects carry flags and alarm flags. It also selects whether to generate
interrupts for each flag.
RCR1 is initialized to H'00 by a power-on reset or a manual reset, all bits are initialized to 0
except for the CF flag, which is undefined. When using the CF flag, it must be initialized
beforehand. This register is not initialized in standby mode.
Bit
7
6, 5
Bit Name
CF
—
Initial Value
Undefined
All 0
R/W
R/W
R
Description
Carry Flag
Status flag that indicates that a carry has
occurred. CF is set to 1 when a count-up to 64-
Hz occurs at the second counter carry or 64-Hz
counter read. A count register value read at this
time cannot be guaranteed; another read is
required.
0: No carry of 64-Hz counter by second counter
1: Carry of 64-Hz counter by second counter or
Reserved
These bits are always read as 0. The write value
should always be 0.
or 64-Hz counter
[Clearing condition]
When 0 is written to CF
64 Hz counter
[Setting condition]
When the second counter or 64-Hz counter is
read during a carry occurrence by the 64-Hz
counter, or 1 is written to CF.
Rev. 3.00 Jan. 18, 2008 Page 575 of 1458
Section 17 Realtime Clock (RTC)
REJ09B0033-0300