參數(shù)資料
型號: P87C51X2FA,512
廠商: NXP Semiconductors
文件頁數(shù): 29/62頁
文件大小: 0K
描述: IC 80C51 MCU 128 RAM 44PLCC
標(biāo)準(zhǔn)包裝: 26
系列: 87C
核心處理器: 8051
芯體尺寸: 8-位
速度: 33MHz
連通性: EBI/EMI,UART/USART
外圍設(shè)備: POR
輸入/輸出數(shù): 32
程序存儲器容量: 4KB(4K x 8)
程序存儲器類型: OTP
RAM 容量: 128 x 8
電壓 - 電源 (Vcc/Vdd): 2.7 V ~ 5.5 V
振蕩器型: 內(nèi)部
工作溫度: -40°C ~ 85°C
封裝/外殼: 44-LCC(J 形引線)
包裝: 管件
其它名稱: 568-7911-5
568-7911-5-ND
568-8360-5
935269605512
P87C51X2FA
P87C51X2FA,512-ND
P87C51X2FA-ND
Philips Semiconductors
Product data
P80C3xX2; P80C5xX2;
P87C5xX2
80C51 8-bit microcontroller family
4K/8K/16K/32K ROM/OTP, low voltage (2.7 to 5.5 V),
low power, high speed (30/33 MHz)
2003 Jan 24
35
. . . .
C1
C2
C3
C4
C5
. . . .
Interrupts
Are Polled
Long Call to
Interrupt
Vector Address
Interrupt Routine
ε
Interrupt
Goes
Active
. . . . . . . . .
Interrupt
Latched
This is the fastest possible response when C2 is the final cycle of an instruction other than RETI or an access to IE or IP.
S5P2
S6
. . . . . . . . .
SU00546
Figure 25. Interrupt Response Timing Diagram
The polling cycle/LCALL sequence is illustrated in Figure 25.
Note that if an interrupt of higher priority level goes active prior to
S5P2 of the machine cycle labeled C3 in Figure 25, then in
accordance with the above rules it will be vectored to during C5 and
C6, without any instruction of the lower priority routine having been
executed.
Thus the processor acknowledges an interrupt request by executing
a hardware-generated LCALL to the appropriate servicing routine. In
some cases it also clears the flag that generated the interrupt, and in
other cases it doesn’t. It never clears the Serial Port flag. This has to
be done in the user’s software. It clears an external interrupt flag
(IE0 or IE1) only if it was transition-activated. The
hardware-generated LCALL pushes the contents of the Program
Counter on to the stack (but it does not save the PSW) and reloads
the PC with an address that depends on the source of the interrupt
being vectored to, as shown in Table 8.
Execution proceeds from that location until the RETI instruction is
encountered. The RETI instruction informs the processor that this
interrupt routine is no longer in progress, then pops the top two
bytes from the stack and reloads the Program Counter. Execution of
the interrupted program continues from where it left off.
Note that a simple RET instruction would also have returned
execution to the interrupted program, but it would have left the
interrupt control system thinking an interrupt was still in progress,
making future interrupts impossible.
External Interrupts
The external sources can be programmed to be level-activated or
transition-activated by setting or clearing bit IT1 or IT0 in Register
TCON. If ITx = 0, external interrupt x is triggered by a detected low
at the INTx pin. If ITx = 1, external interrupt x is edge triggered. In
this mode if successive samples of the INTx pin show a high in one
cycle and a low in the next cycle, interrupt request flag IEx in TCON
is set. Flag bit IEx then requests the interrupt.
Since the external interrupt pins are sampled once each machine
cycle, an input high or low should hold for at least 12 oscillator
periods to ensure sampling. If the external interrupt is
transition-activated, the external source has to hold the request pin
high for at least one cycle, and then hold it low for at least one cycle.
This is done to ensure that the transition is seen so that interrupt
request flag IEx will be set. IEx will be automatically cleared by the
CPU when the service routine is called.
If the external interrupt is level-activated, the external source has to
hold the request active until the requested interrupt is actually
generated. Then it has to deactivate the request before the interrupt
service routine is completed, or else another interrupt will be
generated.
Response Time
The INT0 and INT1 levels are inverted and latched into IE0 and IE1
at S5P2 of every machine cycle. The values are not actually polled
by the circuitry until the next machine cycle. If a request is active
and conditions are right for it to be acknowledged, a hardware
subroutine call to the requested service routine will be the next
instruction to be executed. The call itself takes two cycles. Thus, a
minimum of three complete machine cycles elapse between
activation of an external interrupt request and the beginning of
execution of the first instruction of the service routine. Figure 25
shows interrupt response timings.
A longer response time would result if the request is blocked by one
of the 3 previously listed conditions. If an interrupt of equal or higher
priority level is already in progress, the additional wait time obviously
depends on the nature of the other interrupt’s service routine. If the
instruction in progress is not in its final cycle, the additional wait time
cannot be more the 3 cycles, since the longest instructions (MUL
and DIV) are only 4 cycles long, and if the instruction in progress is
RETI or an access to IE or IP, the additional wait time cannot be
more than 5 cycles (a maximum of one more cycle to complete the
instruction in progress, plus 4 cycles to complete the next instruction
if the instruction is MUL or DIV).
Thus, in a single-interrupt system, the response time is always more
than 3 cycles and less than 9 cycles.
As previously mentioned, the derivatives described in this data
sheet have a four-level interrupt structure. The corresponding
registers are IE, IP and IPH. (See Figures 22, 23, and 24.) The IPH
(Interrupt Priority High) register makes the four-level interrupt
structure possible.
The function of the IPH SFR is simple and when combined with the
IP SFR determines the priority of each interrupt. The priority of each
interrupt is determined as shown in the following table:
PRIORITY BITS
INTERRUPT PRIORITY LEVEL
IPH.x
IP.x
INTERRUPT PRIORITY LEVEL
0
Level 0 (lowest priority)
0
1
Level 1
1
0
Level 2
1
Level 3 (highest priority)
相關(guān)PDF資料
PDF描述
C8051F560-IQ IC 8051 MCU 32K FLASH 32-QFP
C8051F931-GM IC 8051 MCU 64K FLASH 24-QFN
P87LPC762FD,512 IC 80C51 MCU 2K OTP 20-SOIC
MC68HC908JK3CP IC MCU 8MHZ 4K FLASH 20-DIP
MC68HC908JK3CDW IC MCU 8MHZ 4K FLASH 20-SOIC
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
P87C52 制造商:Intel 功能描述:
P87C52-1 制造商:. 功能描述:
P87C521FFFA 制造商:PHILIP 功能描述:
P87C521SF76 功能描述:IC MCU 8BIT 5V 16MZ OTP 44DIP RoHS:否 類別:集成電路 (IC) >> 嵌入式 - 微控制器, 系列:87C 其它有關(guān)文件:STM32F101T8 View All Specifications 特色產(chǎn)品:STM32 32-bit Cortex MCUs 標(biāo)準(zhǔn)包裝:490 系列:STM32 F1 核心處理器:ARM? Cortex?-M3 芯體尺寸:32-位 速度:36MHz 連通性:I²C,IrDA,LIN,SPI,UART/USART 外圍設(shè)備:DMA,PDR,POR,PVD,PWM,溫度傳感器,WDT 輸入/輸出數(shù):26 程序存儲器容量:64KB(64K x 8) 程序存儲器類型:閃存 EEPROM 大小:- RAM 容量:10K x 8 電壓 - 電源 (Vcc/Vdd):2 V ~ 3.6 V 數(shù)據(jù)轉(zhuǎn)換器:A/D 10x12b 振蕩器型:內(nèi)部 工作溫度:-40°C ~ 85°C 封裝/外殼:36-VFQFN,36-VFQFPN 包裝:托盤 配用:497-10030-ND - STARTER KIT FOR STM32497-8853-ND - BOARD DEMO STM32 UNIV USB-UUSCIKSDKSTM32-PL-ND - KIT IAR KICKSTART STM32 CORTEXM3497-8512-ND - KIT STARTER FOR STM32F10XE MCU497-8505-ND - KIT STARTER FOR STM32F10XE MCU497-8304-ND - KIT STM32 MOTOR DRIVER BLDC497-6438-ND - BOARD EVALUTION FOR STM32 512K497-6289-ND - KIT PERFORMANCE STICK FOR STM32MCBSTM32UME-ND - BOARD EVAL MCBSTM32 + ULINK-MEMCBSTM32U-ND - BOARD EVAL MCBSTM32 + ULINK2更多... 其它名稱:497-9032STM32F101T8U6-ND
P87C52-2 制造商:INTEL 制造商全稱:Intel Corporation 功能描述:CHMOS SINGLE-CHIP 8-BIT MICROCONTROLLER