参数资料
型号: P83C576EBAA
厂商: NXP SEMICONDUCTORS
元件分类: 微控制器/微处理器
英文描述: 80C51 8-bit microcontroller family 8K/256 OTP/ROM, 6 channel 10-bit A/D, 4 comparators, failure detect circuitry, watchdog timer
中文描述: 8-BIT, MROM, 16 MHz, MICROCONTROLLER, PQCC44
封装: PLASTIC, MO-047AC, SOT-187-2, LCC-44
文件页数: 9/46页
文件大小: 447K
代理商: P83C576EBAA
Philips Semiconductors
Product specification
83C576/87C576
80C51 8-bit microcontroller family
8K/256 OTP/ROM, 6 channel 10-bit A/D, 4 comparators,
failure detect circuitry, watchdog timer
1998 Jun 04
9
Table 1.
87C576 Special Function Registers
(Continued)
SYMBOL
DESCRIPTION
DIRECT
ADDRESS
BIT ADDRESS, SYMBOL, OR ALTERNATIVE PORT FUNCTION
MSB
LSB
RESET
VALUE
TH0
TH1
TH2#
TL0
TL1
TL2#
Timer High 0
Timer High 1
Timer High 2
Timer Low 0
Timer Low 1
Timer Low 2
8CH
8DH
CDH
8AH
8BH
CCH
00H
00H
00H
00H
00H
00H
TMOD
UCS#
Timer Mode
UPI Control/Status
89H
86H
GATE
ST7
C/T
ST6
M1
ST5
M0
ST4
GATE
UE
C/T
AF
M1
IBF
M0
00H
00H
OBE/OBF
WDCON
#
Watchdog Timer Control
C4H
PRE2
PRE1
PRE0
LVRE
OFRE
DPD
WDRUN
WDMOD
11111111B
WDL#
WFEED1#
WFEED2#
*
SFRs are bit addressable.
#
SFRs are modified from or added to the 80C51 SFRs.
1. Reset value depends on reset source.
Watchdog Timer Reload
Watchdog Feed 1
Watchdog Feed 2
C1H
C2H
C3H
00H
xxH
xxH
The 8XC576 has a number of failure detect circuits to prevent
abnormal operating conditions. these failure detect circuits generate
resets as shown in Figure 1.
POWER ON CLEAR / POWER ON FLAG
An on-chip Power On Detect Circuit resets the 8XC576 and sets the
Power Off Flag (PCON.4) on power up or if V
CC
drops to zero
momentarily. The POF can only be cleared by software. The RST
pin is not driven by the power on detect circuit. The POF can be
read by software to determine that a power failure has occurred and
can also be set by software.
LOW VOLTAGE DETECT
An on-chip Low Voltage Detect circuit sets the Low Voltage Flag
(PCON.3) if V
CC
drops below V
LOW
(see DC Electrical
Characteristics) and resets the 8XC576 if the Low Voltage Reset
Enable bit (WDCON.4) is set. If the LVRE is cleared, the reset is
disabled but LVF will still be set if V
CC
is low. The RST pin is not
driven by the low voltage detect circuit. The LVF can be read by
software to determine that V
CC
was low. The LVF can be set or
cleared by software.
OSCILLATOR FAIL DETECT
An on-chip Oscillator Fail Detect circuit sets the Oscillator Fail Flag
(PCON.5) if the oscillator frequency drops below OSCF for one or
more cycles (see AC Electrical Characteristics: OSCF) and resets
the 8XC576 if the Oscillator Fail Reset Enable bit (WDCON.3) is set.
If OFRE is cleared, the reset is disabled but OSF will still be set if
the oscillator fails. The RST pin is not driven by the oscillator fail
detect circuit. The OSF can be read by software to determine that
an oscillator failure has occurred. The OSF can be set or cleared by
software.
LOW ACTIVE RESET
One of the most notable features on this part is the low active reset.
The low active reset operates exactly the same as high active reset
with the exception that the part is put into the reset mode by
applying a low level to the reset pin. For power-on reset it is also
necessary to invert the power-on reset circuit; connecting the 8.2K
resistor from the reset pin to V
CC
and the 10
μ
f capacitor from the
reset pin to ground. Figure 1 shows the reset related circuitry.
When reset the port pins on the 8XC576 are driven high
synchronously.
The 8XC576 also has Low voltage detection circuitry that will, if
enabled, force the part to reset when V
CC
(on the part) fails below a
set level. Low Voltage Reset is enabled by a normal reset. Low
Voltage Reset can be disabled by clearing LVRE (bit 4 in the
WDCON SFR) then executing a watchdog feed sequence (A5H to
WFEED1 followed immediately by 5AH to WFEED2). In addition
there is a flag (LVF) that is set if a low voltage condition is detected.
The LVF flag is set even if the Low Voltage detection circuitry is
disabled. Notice that the Low voltage detection circuitry does not
drive the RST# pin so the LVF flag is the only way that the
microcontroller can determine if it has been reset due to a low
voltage condition.
The 8XC576 has an on-chip power-on detection circuit that sets the
POF (PCON.4) flag on power up or if the V
CC
level momentarily
drops to 0V. This flag can be used to determine if the part is being
started from a power-on (cold start) or if a reset has occurred due to
another condition (warm start).
The 8XC576 can be reset in software by setting the RST bit of the
AUXR register (AUXR.3). See Figure 1 for reset diagram.
相关PDF资料
PDF描述
P83C576EHPN 80C51 8-bit microcontroller family 8K/256 OTP/ROM, 6 channel 10-bit A/D, 4 comparators, failure detect circuitry, watchdog timer
P87C576EHPN 80C51 8-bit microcontroller family 8K/256 OTP/ROM, 6 channel 10-bit A/D, 4 comparators, failure detect circuitry, watchdog timer
P83C576EBBB 80C51 8-bit microcontroller family 8K/256 OTP/ROM, 6 channel 10-bit A/D, 4 comparators, failure detect circuitry, watchdog timer
P87C576EBBB 80C51 8-bit microcontroller family 8K/256 OTP/ROM, 6 channel 10-bit A/D, 4 comparators, failure detect circuitry, watchdog timer
P87C576EBAA 80C51 8-bit microcontroller family 8K/256 OTP/ROM, 6 channel 10-bit A/D, 4 comparators, failure detect circuitry, watchdog timer
相关代理商/技术参数
参数描述
P83C576EBB 制造商:未知厂家 制造商全称:未知厂家 功能描述:8-Bit Microcontroller
P83C576EBBB 制造商:PHILIPS 制造商全称:NXP Semiconductors 功能描述:80C51 8-bit microcontroller family 8K/256 OTP/ROM, 6 channel 10-bit A/D, 4 comparators, failure detect circuitry, watchdog timer
P83C576EBN 制造商:未知厂家 制造商全称:未知厂家 功能描述:Microcontroller
P83C576EBP 制造商:未知厂家 制造商全称:未知厂家 功能描述:8-Bit Microcontroller
P83C576EBPN 制造商:PHILIPS 制造商全称:NXP Semiconductors 功能描述:80C51 8-bit microcontroller family 8K/256 OTP/ROM, 6 channel 10-bit A/D, 4 comparators, failure detect circuitry, watchdog timer