M16C65 Datasheet, PDF (445/829 Pages) Renesas Technology Corp – RENESAS MCU M16C FAMILY / M16C/60

Under development
M16C/65 Group
Preliminary Specification
This is a preliminary specification and is subject to change.
20.2.5 Real-Time Clock Control Register 1 (RTCCR1)
20. Real-Time Clock
Real-Time Clock Control Register 1
b7 b6 b5 b4 b3 b2 b1 b0
0
Symbol
RTCCR1
Address
0344h
After Reset
0000 X00Xb
Bit Symbol
Bit Name
Function
RW
—
(b0)
Reserved bit
Set to 0
RW
TCSTF
Real-time clock count status
flag
0 : Count stopped
1 : Counting
RO
TOENA RTCOUT pin output bit
0 : Compare output disabled
1 : Compare output enabled
RW
—
(b3)
Reserved bit
Set to 0
RW
RTCRST Real-time clock reset bit
Setting this bit to 0 after setting it to 1
resets the real-time clock
RW
RTCPM A.m./p.m. bit
0 : a.m.
1 : p.m.
RW
H12H24 Operating mode select bit
0 : 12-hour mode
1 : 24-hour mode
RW
TSTART
Real-time clock count start bit
0 : Count stops
1 : Count starts
RW
TCSTF (Real-Time Clock Count Status Flag) (b1)
TSTART (Real-Time Clock Count Start Bit) (b7)
The real-time clock has the TSTART bit for instructing the count to start or stop, and the TCSTF bit,
which indicates count start or stop.
The real-time clock starts counting and the TCSTF bit becomes 1 (count starts) when the TSTART bit is
set to 1 (count starts). It takes up to two cycles of the count source until the TCSTF bit becomes 1 after
setting the TSTART bit to 1. During this time, do not access registers associated with the real-time clock
(1) _{other than the TCSTF bit.}
Also, when setting the TSTART bit to 0 (count stops), the real-time clock stops counting and the TCSTF
bit becomes 0 (count stops). It takes the time for up to three cycles of the count source until the TCSTF
bit becomes 0 after setting the TSTART bit to 0. During this time, do not access registers associated
with the real-time clock ⁽¹⁾ other than the TCSTF bit.
Note:
1. Registers associated with the real-time clock: RTCSEC, RTCMIN, RTCHR, RTCWK, RTCCR1,
RTCCR2, and RTCCSR.
REJ09B0484-0030 Rev.0.30 Sep 09, 2008
Page 410 of 791