ADUC7121 Analog Devices, ADUC7121 Datasheet - Page 93

• Manufacturer Part Number: ADUC7121
• Description: Precision Analog Microcontroller, 12-Bit Analog I/O, ARM7TDMI MCU
• Manufacturer: Analog Devices

Specifications of ADUC7121

• Mcu Core: ARM7 TDMI
• Mcu Speed (mips): 40
• Sram (bytes): 8192Bytes
• Gpio Pins: 32
• Adc # Channels: 9

TIMER4—GENERAL-PURPOSE TIMER
Timer4 is a 32-bit general-purpose timer, count down or count
up, with a programmable prescaler. The prescaler source can be
the 32 kHz oscillator, the core clock, or PLL undivided output. This
source can be scaled by a factor of 1, 16, 256, or 32,768. This
gives a minimum resolution of 42 ns when operating at CD
zero, the core is operating at 41.78 MHz, and with a prescaler of 1
(ignoring external GPIO).
The counter can be formatted as a standard 32-bit value or as
hours:minutes:seconds:hundreths.
Timer4 has a capture register (T4CAP), which can be triggered
by a selected IRQ’s source initial assertion. Once triggered, the
current timer value is copied to T4CAP, and the timer keeps
running. This feature can be used to determine the assertion of
an event with increased accuracy.
Timer4 interface consists of five MMRS.
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•
•
•
Timer4 reloads the value from T4LD either when Timer4
overflows, or immediately when T4ICLR is written.
Timer4 Load Registers
T4LD is a 32-bit register, which holds the 32-bit value that is
loaded into the counter.
Name:
Address:
Default value:
Access:
Note that if the part is in a low power mode, and Timer4 is
clocked from the GPIO or oscillator source then, Timer4
continues to operate.
T4LD, T4VAL and T4CAP are 32-bit registers and hold 32-
bit unsigned integers. T4VAL and T4CAP are read only.
T4ICLR is an 8-bit register. Writing any value to this
register clears the Timer1 interrupt.
T4CON is the configuration MMR.
T4LD
0xFFFF0380
0x00000000
Read and write
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Timer4 Clear Register
This 8-bit, write-only MMR is written (with any value) by user
code to refresh (reload) Timer4.
Name:
Address:
Default value:
Access:
Timer4Value Register
T4VAL is a 32-bit register that holds the current value of
Timer4.
Name:
Address:
Default value:
Access:
Timer4 Capture Register
This is a 32-bit register that holds the 32-bit value captured by
an enabled IRQ event.
Name:
Address:
Default value:
Access:
Timer4 Control Register
This 32-bit MMR configures the mode of operation of Timer4.
Name:
Address:
Default value:
Access:
T4CLRI
0xFFFF038C
0x00
Write only
T4VAL
0xFFFF0384
0x00000000
Read only
T4CAP
0xFFFF0390
0x00000000
Read only
T4CON
0xFFFF0388
0x0000
Read and write
ADuC7121