DS07-16303-3E Datasheet, PDF (42/97 Pages) Fujitsu Component Limited. – 32-bit RISC Microcontroller CMOS FR30 Series

MB91121
4. U-TIMER (16-bit Timer for UART Baud Rate Generation)
The U-TIMER is a 16-bit timer for generating UART baud rate. Combination of chip operating frequency and
reload value of U-TIMER allows flexible setting of baud rate.
The U-TIMER operates as an interval timer by using interrupt issued on counter underflow.
The MB91121 has 3 channel U-TIMER embedded on the chip. An interval of up to 2¹⁶ × φ can be counted.
• Block diagram
bit 15
bit 15
φ
(Peripheral clock)
UTIMR (reload register)
Load
UTIM ( U-TIMER register)
Clock
Underflow
f.f.
bit 0
bit 0
Control
To UART
• Register configuration
Address
00000078H
00000079H
bit 15
UTIM0/UTIMR0
Initial value
bit 0
0 0 0 0 0 0 0 0B (R/W)
0 0 0 0 0 0 0 0B
0000007CH
0000007DH
UTIM1/UTIMR1
0 0 0 0 0 0 0 0B (R/W)
0 0 0 0 0 0 0 0B
00000080H
00000081H
0000007BH
0000007FH
00000083H
UTIM2/UTIMR2
UTIMC0
UTIMC1
UTIMC2
0 0 0 0 0 0 0 0B (R/W)
0 0 0 0 0 0 0 0B
0 − − 0 0 0 0 1B (R/W)
0 − − 0 0 0 0 1B (R/W)
0 − − 0 0 0 0 1B (R/W)
( ) : Access
R/W : Readable and writable
 : Unused
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