EG87C51FA1SF76 Intel, EG87C51FA1SF76 Datasheet - Page 6

• Manufacturer Part Number: EG87C51FA1SF76
• Description: IC MCU 8-BIT 8K 16MHZ OTP 44MQFP
• Manufacturer: Intel
• Series: 87Cr

Specifications of EG87C51FA1SF76

• Core Processor: MCS 51
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: SIO
• Peripherals: PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: OTP
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-MQFP, 44-PQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Data Converters: -
• Other names: 864517

8XC51FX
IDLE MODE
The user’s software can invoke the Idle Mode When
the microcontroller is in this mode power consump-
tion is reduced The Special Function Registers and
the onboard RAM retain their values during Idle but
the processor stops executing instructions Idle
Mode will be exited if the chip is reset or if an en-
abled interrupt occurs The PCA timer counter can
optionally be left running or paused during Idle
Mode
POWER DOWN MODE
To save even more power a Power Down mode can
be invoked by software In this mode the oscillator
is stopped and the instruction that invoked Power
NOTE
For more detailed information on the reduced power modes refer to current Embedded Microcontrollers and Processors
Handbook Volume I and Application Note AP-252 (Embedded Applications Handbook) ‘‘Designing with the 80C51BH ’’
6
C1 C2
For Ceramic Resonators contact resonator manufacturer
Figure 4 External Clock Drive Configuration
Idle
Idle
Power Down
Power Down
Mode
e
Figure 3 Oscillator Connections
30 pF
g
10 pF for Crystals
Table 2 Status of the External Pins during Idle and Power Down
Program
Memory
External
External
Internal
Internal
ALE
1
1
0
0
272322 –3
272322–4
PSEN
1
1
0
0
Down is the last instruction executed The on-chip
RAM and Special Function Registers retain their val-
ues until the Power Down mode is terminated
On the 8XC51FX either hardware reset or external
interrupt can cause an exit from Power Down Reset
redefines all the SFRs but does not change the on-
chip RAM An external interrupt allows both the
SFRs and the on-chip RAM to retain their values
To properly terminate Power Down the reset or ex-
ternal interrupt should not be executed before V
restored to its normal operating level and must be
held active long enough for the oscillator to restart
and stabilize (normally less than 10 ms)
With an external interrupt INT0 or INT1 must be en-
abled and configured as level-sensitive Holding the
pin low restarts the oscillator but bringing the pin
back high completes the exit Once the interrupt is
serviced the next instruction to be executed after
RETI will be the one following the instruction that put
the device into Power Down
DESIGN CONSIDERATION
PORT0
Float
Float
Data
Data
Ambient light is known to affect the internal RAM
contents during operation If the 87C51FX appli-
cation requires the part to be run under ambient
lighting an opaque label should be placed over
the window to exclude light
When the idle mode is terminated by a hardware
reset the device normally resumes program exe-
cution from where it left off up to two machine
cycles before the internal reset algorithm takes
control On-chip hardware inhibits access to inter-
nal RAM in this event but access to the port pins
is not inhibited To eliminate the possibility of an
unexpected write when Idle is terminated by re-
set the instruction following the one that invokes
Idle should not be one that writes to a port pin or
to external memory
PORT1
Data
Data
Data
Data
Address
PORT2
Data
Data
Data
PORT3
Data
Data
Data
Data
CC
is