ADUC7122 Analog Devices, ADUC7122 Datasheet - Page 48

• Manufacturer Part Number: ADUC7122
• Description: Precision Analog Microcontroller, 12-Bit Analog I/O, ARM7TDMI® MCU
• Manufacturer: Analog Devices

Specifications of ADUC7122

• Mcu Core: ARM7 TDMI
• Mcu Speed (mips): 40
• Sram (bytes): 8192Bytes
• Gpio Pins: 32
• Adc # Channels: 13

ADuC7122
MMRS AND KEYS
To prevent accidental programming, a certain sequence must be
followed when writing in the PLLCON and POWCON registers
(see Table 74).
Table 70. PLLKEYx Register
Name
PLLKEY1
PLLKEY2
Table 71. PLLCON Register
Name
PLLCON
Table 72. POWKEYx Register
Name
POWKEY1
POWKEY2
Table 73. POWCON Register
Name
POWCON
Table 74. PLLCON and POWCON Write Sequence
PLLCON
PLLKEY1 = 0xAA
PLLCON = 0x01
PLLKEY2 = 0x55
Address
0xFFFF0404
0xFFFF040C
Address
0xFFFF0410
0xFFFF0418
Address
0xFFFF0414
Address
0xFFFF0408
Default Value
0x0000
0x0000
Default Value
0x21
Default Value
0x03
Default Value
0x0000
0x0000
POWCON
POWKEY1 = 0x01
POWCON = user value
POWKEY2 = 0xF4
Access
W
W
Access
R/W
Access
R/W
Access
W
W
Rev. 0 | Page 48 of 96
Table 75. PLLCON MMR Bit Designations
Bit
7:6
5
4:2
1:0
Table 76. POWCON MMR Bit Designations
Bit
7
6:4
3
2:0
Value
000
001
010
011
100
Others
000
001
010
011
100
101
110
111
Value
1
0
00
01
10
11
Name
PC
RSVD
CD
Name
OSEL
MDCLK
Description
Reserved.
Operating modes.
Active mode.
Pause mode.
Nap.
Sleep mode. IRQ0 to IRQ3 and Timer2
can wake up the ADuC7122.
Stop mode.
Reserved.
Reserved.
CPU clock divider bits.
41.779200 MHz.
20.889600 MHz.
10.444800 MHz.
5.222400 MHz.
2.611200 MHz.
1.305600 MHz.
654.800 kHz.
326.400 kHz.
Description
Reserved.
32 kHz PLL input selection.
Cleared by the user to use the
external 32 kHz crystal.
Reserved.
Clocking modes.
Reserved.
PLL. default configuration.
Reserved.
External clock on P1.4 pin.
Set by the user to use the internal
32 kHz oscillator. Set by default.