MB91F376G Fujitsu Components, MB91F376G Datasheet - Page 180

• Manufacturer Part Number: MB91F376G
• Manufacturer: Fujitsu Components

Specifications of MB91F376G

• Lead Free Status / Rohs Status: Not Compliant

180
MB91360G Series
28. 32 kHz Clock Calibration Unit
(1) Description
(2) Block diagram
RSLEEP
The 32 kHz Clock Calibration Module provides possibilities to calibrate the 32 kHz oscillation clock with respect
to the 4 MHz oscillation clock.
This hardware allows the software to measure time generated by the 32 kHz clock with the 4 MHz clock.
By utilizing this hardware in conjunction with software processing, the accuracy of the 32 kHz clock can come
closer to that of the 4 MHz clock. The measurement result from the 32 kHz Clock Calibration Module can be
processed by the software and the setting required for the Real Time Clock Module can be obtained.
This module consists of two timers, one operating with the 32 kHz clock and the other operating with the 4 MHz
clock. The 32 kHz timer triggers the 4 MHz timer and resulting 4 MHz timer value is stored in a register. The
value stored in this register can be used for the subsequent software processing to calculate the desired Real
Time Clock module’s setting.
OSC32
OSC4
CLKP
*_WR
RMW
*_RD
RST
INT
RB
SLKPG2 = CLKP
RSLEEPB
RSLEEPB
| (∼STRT & RSLEEPB) ;
READY
RUNS
STRT
STRT
STRT
UC18CLK
gate
gate
gate
gate
UC18BUS
UC18I/O
STRT
async
RST
CLK4G = OSC4 | ∼ STRT | (READY & −RUNS) ;
CLKPG
CLKPG2
RB
CLKP ≥ 32
RBB
RSLEEPB
RMWB
INT_I
*_RDB
*_WRB
RSTB
sync
CLK32G
STRTS
CUTD
STRT
counter (16 bit)
&
STRT
32 kHz
TIMER
&
RUN
INT_INT
READY
UC18TRD
anync
RST
set
/reset
set
/reset
reset
CUTD (16 bit)
CUTR (24 bit)
CUCR (3 bit)
INTEN
STRT
INT
32 ≥ 4
RUN
sync
reset
CLK4G
set
RUNS
VC18RBI
READY-
PULSE
CUTD
&
CUTR (24 bit)
READY
RUNSS1
RUNSS
TIMER
4 MHz
UC18TRR
4 ≥ CLKP
sync
CUTR