SH7720 Datasheet, PDF (628/1524 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7700 Series

Section 17 Realtime Clock (RTC)
17.3.4 Hour Counter (RHRCNT)
RHRCNT is used for setting/counting in the BCD-coded hour section. The count operation is
performed by a carry for each 1 hour of the minute counter.
The range of hour can be set is 00 to 23 (decimal). Errant operation will result if any other value is
set. Carry out write processing after stopping the count operation with the START bit in RCR2.
RHRCNT is not initialized by a power-on reset or manual reset, or in standby mode.
Bit
7, 6
5, 4
3 to 0
Bit Name

Initial Value R/W
All 0
R

Undefined R/W

Undefined R/W
Description
Reserved
These bits are always read as 0. Though writing
has no effect, the write value should always be 0.
Counting Ten’s Position of Hours
Counts on 0 to 2 for ten’s position of hours.
Counting One’s Position of Hours
Counts on 0 to 9 once per hour. When a carry is
generated, 1 is added to the ten’s position.
Rev. 3.00 Jan. 18, 2008 Page 566 of 1458
REJ09B0033-0300