AT87F55WD-24JI Atmel, AT87F55WD-24JI Datasheet - Page 6
![IC MICRO CTRL 24MHZ 44PLCC](/photos/6/70/67043/453-44-plcc_sml.jpg)
AT87F55WD-24JI
Manufacturer Part Number
AT87F55WD-24JI
Description
IC MICRO CTRL 24MHZ 44PLCC
Manufacturer
Atmel
Series
87Fr
Datasheet
1.AT87F55WD-24AC.pdf
(26 pages)
Specifications of AT87F55WD-24JI
Core Processor
8051
Core Size
8-Bit
Speed
24MHz
Connectivity
UART/USART
Peripherals
WDT
Number Of I /o
32
Program Memory Size
20KB (20K x 8)
Program Memory Type
OTP Quick FLASH
Ram Size
256 x 8
Voltage - Supply (vcc/vdd)
4 V ~ 5.5 V
Oscillator Type
Internal
Operating Temperature
-40°C ~ 85°C
Package / Case
44-PLCC
Lead Free Status / RoHS Status
Contains lead / RoHS non-compliant
Eeprom Size
-
Data Converters
-
Other names
AT87F55WD24JI
Table 3a. AUXR: Auxiliary Register
Dual Data Pointer Registers: To facilitate accessing both
internal and external data memory, two banks of 16-bit
Data Pointer Registers are provided: DP0 at SFR address
locations 82H-83H and DP1 at 84H-85H. Bit DPS = 0 in
SFR AUXR1 selects DP0 and DPS = 1 selects DP1.
The user should always initialize the DPS bit to the appro-
priate value before accessing the respective Data Pointer
Register.
Table 3b. AUXR1: Auxiliary Register 1
6
AUXR
–
DISALE
DISTRO
WDIDLE
AUXR1
–
DPS
Reserved for future expansion
Disable/Enable ALE
DISALE
0
1
Disable/Enable Reset out
DISRTO
0
1
Disable/Enable WDT in IDLE mode
WDIDLE
0
1
Reserved for future expansion
Data Pointer Register Select
DPS
0
1
Address = 8EH
Not Bit Addressable
Address = A2H
Not Bit Addressable
Bit
Bit
AT87F55WD
Operating mode
ALE is emitted at a constant rate of 1/6 the oscillator frequency
ALE is active only during a MOVX or MOVC instruction
Reset pin is driven High after WDT times out
Reset pin is input only
WDT continues to count in IDLE mode
WDT halts counting in IDLE mode
Selects DPTR Registers DP0L, DP0H
Selects DPTR Registers DP1L, DP1H
–
7
–
7
–
6
–
6
–
5
–
5
WDIDLE
4
–
4
Power Off Flag: The Power Off Flag (POF) is located at bit
4 (PCON.4) in the PCON SFR. POF is set to “1” during
power up. It can be set and rest under software control and
is not affected by reset.
DISRTO
3
–
3
–
2
–
2
Reset Value = XXXXXXX0B
Reset Value = XXX00XX0B
–
1
–
1
DISALE
DPS
0
0