- 您现在的位置：买卖IC网 > PDF目录80479 > MC68HLC908QT4CFQ (MOTOROLA INC) 8-BIT, FLASH, 2 MHz, MICROCONTROLLER, PQCC8 PDF资料下载
参数资料
| 型号： | MC68HLC908QT4CFQ |
| 厂商： | MOTOROLA INC |
| 元件分类： | 微控制器/微处理器 |
| 英文描述： | 8-BIT, FLASH, 2 MHz, MICROCONTROLLER, PQCC8 |
| 封装： | DFN-8 |
| 文件页数： | 163/186页 |
| 文件大小： | 2583K |
| 代理商： | MC68HLC908QT4CFQ |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页第36页第37页第38页第39页第40页第41页第42页第43页第44页第45页第46页第47页第48页第49页第50页第51页第52页第53页第54页第55页第56页第57页第58页第59页第60页第61页第62页第63页第64页第65页第66页第67页第68页第69页第70页第71页第72页第73页第74页第75页第76页第77页第78页第79页第80页第81页第82页第83页第84页第85页第86页第87页第88页第89页第90页第91页第92页第93页第94页第95页第96页第97页第98页第99页第100页第101页第102页第103页第104页第105页第106页第107页第108页第109页第110页第111页第112页第113页第114页第115页第116页第117页第118页第119页第120页第121页第122页第123页第124页第125页第126页第127页第128页第129页第130页第131页第132页第133页第134页第135页第136页第137页第138页第139页第140页第141页第142页第143页第144页第145页第146页第147页第148页第149页第150页第151页第152页第153页第154页第155页第156页第157页第158页第159页第160页第161页第162页当前第163页第164页第165页第166页第167页第168页第169页第170页第171页第172页第173页第174页第175页第176页第177页第178页第179页第180页第181页第182页第183页第184页第185页第186页
External Interrupt (IRQ)
Data Sheet
MC68HLC908QY/QT Family — Rev. 2
78
External Interrupt (IRQ)
MOTOROLA
8.4 IRQ Pin
A falling edge on the IRQ pin can latch an interrupt request into the IRQ latch. A
vector fetch, software clear, or reset clears the IRQ latch.
If the MODE bit is set, the IRQ pin is both falling-edge sensitive and low-level
sensitive. With MODE set, both of the following actions must occur to clear IRQ:
Vector fetch or software clear — A vector fetch generates an interrupt
acknowledge signal to clear the latch. Software may generate the interrupt
acknowledge signal by writing a 1 to the ACK bit in the interrupt status and
control register (INTSCR). The ACK bit is useful in applications that poll the
IRQ pin and require software to clear the IRQ latch. Writing to the ACK bit
prior to leaving an interrupt service routine can also prevent spurious
interrupts due to noise. Setting ACK does not affect subsequent transitions
on the IRQ pin. A falling edge that occurs after writing to the ACK bit latches
another interrupt request. If the IRQ mask bit, IMASK, is clear, the CPU
loads the program counter with the vector address at locations $FFFA and
$FFFB.
Return of the IRQ pin to logic 1 — As long as the IRQ pin is at logic 0, IRQ
remains active.
The vector fetch or software clear and the return of the IRQ pin to logic 1 may occur
in any order. The interrupt request remains pending as long as the IRQ pin is at
logic 0. A reset will clear the latch and the MODE control bit, thereby clearing the
interrupt even if the pin stays low.
If the MODE bit is clear, the IRQ pin is falling-edge sensitive only. With MODE
clear, a vector fetch or software clear immediately clears the IRQ latch.
The IRQF bit in the INTSCR register can be used to check for pending interrupts.
The IRQF bit is not affected by the IMASK bit, which makes it useful in applications
where polling is preferred.
NOTE:
When the IRQ function is enabled in the CONFIG2 register, the BIH and BIL
instructions can be used to read the logic level on the IRQ pin. If the IRQ function
is disabled, these instructions will behave as if the IRQ pin is a logic 1, regardless
of the actual level on the pin. Conversely, when the IRQ function is enabled, bit 2
of the port A data register will always read a 0.
NOTE:
When using the level-sensitive interrupt trigger, avoid false interrupts by masking
interrupt requests in the interrupt routine. An internal pullup resistor to VDD is
connected to the IRQ pin; this can be disabled by setting the IRQPUD bit in the
CONFIG2 register ($001E).
8.5 IRQ Module During Break Interrupts
The system integration module (SIM) controls whether the IRQ latch can be
cleared during the break state. The BCFE bit in the break flag control register
(BFCR) enables software to clear the latches during the break state. See
相关PDF资料 |
PDF描述 |
|---|---|
| MC68HLC908QY1CDT | 8-BIT, FLASH, 2 MHz, MICROCONTROLLER, PDSO16 |
| MC68HC11F1CFN2R2 | 8-BIT, EEPROM, 2 MHz, MICROCONTROLLER, PQCC68 |
| MC8641DVU1333JC | 32-BIT, 166.66 MHz, MICROPROCESSOR, CBGA1023 |
| MC8641DVU1500KB | 32-BIT, 166.66 MHz, MICROPROCESSOR, CBGA1023 |
| MC68HC711K4MFU3 | 8-BIT, OTPROM, 3 MHz, MICROCONTROLLER, PQFP80 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| MC68HLC908QY1CDW | 制造商:Rochester Electronics LLC 功能描述:LOW V-1.5K FLASH W/O ADC - Bulk |
| MC68HLC908QY1DT | 制造商:Rochester Electronics LLC 功能描述:- Tape and Reel |
| MC68HLC908QY2CDT | 制造商:Rochester Electronics LLC 功能描述:- Bulk |
| MC68HLC908QY2CDW | 制造商:Rochester Electronics LLC 功能描述:LOW V-1.5K FLASH W/ADC - Bulk |
| MC68HLC908QY2CP | 制造商:Rochester Electronics LLC 功能描述:LOW V-1.5K FLASH W/ADC - Bulk |
发布紧急采购，3分钟左右您将得到回复。