HD6417706 RENESAS [Renesas Technology Corp], HD6417706 Datasheet - Page 384

• Manufacturer Part Number: HD6417706
• Description: Renesas 32-Bit RISC Microcomputer Super RISC engine Family/SH7700 Series
• Manufacturer: RENESAS [Renesas Technology Corp]

13.3.15 RTC Control Register 1 (RCR1)
The RTC control register 1 (RCR1) is an 8-bit read/write register that affects carry flags and alarm
flags. It also selects whether to generate interrupts for each flag. Because flags are sometimes set
after an operand read, do not use this register in read-modify-write processing.
RCR1 is initialized to H'00 by a power-on reset. In 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.
Rev. 4.00, 03/04, page 338 of 660
Bit
7
6, 5
4
3
Bit Name
CF
—
CIE
AIE
Initial Value R/W Description
0
All 0
0
0
R/W Carry Flag
R
R/W Carry Interrupt Enable Flag
R/W Alarm Interrupt Enable Flag
Status flag that indicates that a carry has occurred. CF
is set to 1 when a count-up to R64CNT or RSECCNT
occurs. A count register value read at this time cannot
be guaranteed; another read is required.
0: No count up of R64CNT or RSECCNT.
1: Count up of R64CNT or RSECCNT.
Reserved
These bits are always read as 0. The write value should
always be 0.
When the carry flag (CF) is set to 1, the CIE bit enables
interrupts.
0: A carry interrupt is not generated when the CF flag is
1: A carry interrupt is generated when the CF flag is set
When the alarm flag (AF) is set to 1, the AIE bit allows
interrupts.
0: An alarm interrupt is not generated when the AF flag
1: An alarm interrupt is generated when the AF flag is
[Clearing condition]
When 0 is written to CF
[Setting condition]
When 1 is written to CF
set to 1
to 1
is set to 1
set to 1