Rtc Second Alarm Register - Epson S1C17M01 Technical Manual

Cmos 16-bit single chip microcontroller

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Note: When the RTCCTL.RTCTRMBSY bit = 1, the RTCCTL.RTCHLD bit cannot be rewritten to 1

(as fixed at 0).

Bit 4

RTC24H

This bit sets the hour counter to 24H mode or 12H mode.

1 (R/W): 24H mode

0 (R/W): 12H mode

This selection changes the count range of the hour counter. Note, however, that the counter value is

not updated automatically, therefore, it must be programmed again.

Note: Be sure to avoid writing to this bit when the RTCCTL.RTCRUN bit = 1.

Bit 3

Reserved

Bit 2

RTCADJ

This bit executes the 30-second correction time adjustment function.

1 (W):

Execute 30-second correction

0 (W):

Ineffective

1 (R):

30-second correction is executing.

0 (R):

30-second correction has finished. (Normal operation)

Writing 1 to this bit executes 30-second correction and an enabled interrupt occurs even if the RT-

CCTL.RTCRUN bit = 0. The correction takes up to 2/256 seconds. The RTCCTL.RTCADJ bit is

automatically cleared to 0 when the correction has finished. For more information on the 30-second

correction, refer to "Real-Time Clock Counter Operations."

Notes: • Be sure to avoid writing to this bit when the RTCCTL.RTCBSY bit = 1.

• Do not write 1 to this bit again while the RTCCTL.RTCADJ bit = 1.

Bit 1

RTCRST

This bit resets the 1 Hz counter, the RTCCTL.RTCADJ bit, and the RTCCTL.RTCHLD bit.

1 (W):

Reset

0 (W):

Ineffective

1 (R):

Reset is being executed.

0 (R):

Reset has finished. (Normal operation)

This bit is automatically cleared to 0 after reset has finished.

Bit 0

RTCRUN

This bit starts/stops the real-time clock counter.

1 (R/W): Running/start control

0 (R/W): Idle/stop control

When the real-time clock counter stops counting by writing 0 to this bit, the counter retains the value

when it stopped. Writing 1 to this bit again resumes counting from the value retained.