Philips P89LPC908 Interrupt Priority Structure, Summary of Interrupts P89LPC906 Description

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Philips Semiconductors

User’s Manual - Preliminary -

 

 

 

INTERRUPTS

P89LPC906/907/908

3. INTERRUPTS

 

 

The P89LPC906/907/908 use a four priority level interrupt structure. This allows great flexibility in controlling the handling of the many interrupt sources. The P89LPC906 supports 6 interrupt sources: timers 0 and 1, brownout detect, watchdog/ realtime clock, keyboard, and the comparator. The P89LPC907 supports 7 interrupt sources: timers 0 and 1, serial port Tx, brownout detect, watchdog/ realtime clock, keyboard, and comparators 1 and 2. The P89LPC908 supports 9 interrupt sources: timers 0 and 1, serial port Tx, serial port Rx, combined serial port Rx/Tx, brownout detect, watchdog/ realtime clock, keyboard, and comparators 1 and 2.

Each interrupt source can be individually enabled or disabled by setting or clearing a bit in the interrupt enable registers IEN0 or IEN1. The IEN0 register also contains a global enable bit, EA, which enables all interrupts.

Each interrupt source can be individually programmed to one of four priority levels by setting or clearing bits in the interrupt priority registers IP0, IP0H, IP1, and IP1H. An interrupt service routine in progress can be interrupted by a higher priority interrupt, but not by another interrupt of the same or lower priority. The highest priority interrupt service cannot be interrupted by any other interrupt source. If two requests of different priority levels are pending at the start of an instruction, the request of higher priority level is serviced.

If requests of the same priority level are pending at the start of an instruction, an internal polling sequence determines which request is serviced. This is called the arbitration ranking. Note that the arbitration ranking is only used to resolve pending requests of the same priority level.

Table summarizes the interrupt sources, flag bits, vector addresses, enable bits, priority bits, arbitration ranking, and whether each interrupt may wake up the CPU from a Power down mode.

INTERRUPT PRIORITY STRUCTURE

There are four SFRs associated with the four interrupt levels: IP0, IP0H, IP1, IP1H. Every interrupt has two bits in IPx and IPxH (x = 0,1) and can therefore be assigned to one of four levels, as shown in Table .

Table 3-1: Interrupt priority level

Priority Bits

 

 

 

Interrupt Priority Level

 

 

 

 

 

 

 

 

 

IPxH

IPx

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0

0

 

 

 

Level 0 (lowest priority)

 

 

 

 

 

 

 

 

 

 

 

0

1

 

 

 

Level 1

 

 

 

 

 

 

 

 

 

 

 

 

1

0

 

 

 

Level 2

 

 

 

 

 

 

 

 

 

 

 

 

1

1

 

 

 

Level 3 (highest priority)

 

 

 

 

 

 

 

 

 

 

 

Table 3-2: Summary of Interrupts - P89LPC906

 

 

 

 

 

Description

Interrupt

Vector

Interrupt

Interrupt

Arbitration

Power down

Flag Bit(s)

Address

Enable Bit(s)

Priority

Ranking

Wakeup

 

Timer 0 Interrupt

TF0

000Bh

ET0 (IEN0.1)

IP0H.1, IP0.1

3

No

 

 

 

 

 

 

 

Timer 1 Interrupt

TF1

001Bh

ET1 (IEN0.3)

IP0H.3, IP0.3

5

No

 

 

 

 

 

 

 

Brownout Detect

BOF

002Bh

EBO (IEN0.5)

IP0H.5, IP0.5

1

Yes

 

 

 

 

 

 

 

 

 

Watchdog Timer/Real-

WDOVF/

0053h

EWDRT

IP0H.6, IP0.6

2

Yes

time Clock

RTCF

(IEN0.6)

 

 

 

 

 

 

KBI Interrupt

KBIF

003Bh

EKBI (IEN1.1)

IP1H.1, IP1.1

4

Yes

 

 

 

 

 

 

 

Comparator interrupt

CMF

0043h

EC (IEN1.2)

IP1H.2, IP1.2

6

Yes

 

 

 

 

 

 

 

 

 

2003 Dec 8

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Contents User Manual Table of Contents Power-On reset code execution Brownout Detection Power-On Detection Power Reduction Modes103 List of Figures List of Figures P89LPC906 PIN ConfigurationsProduct Comparison Logic SymbolsOscillator Divider Block Diagram P89LPC906KB Code Flash CPUClock Block Diagram P89LPC907Uart Byte Data RAMData RAM Port Block Diagram P89LPC908PIN Descriptions P89LPC906 P1.2 PIN Descriptions P89LPC907P1.0 TxDRxD PIN Descriptions P89LPC908Keyboard Input P1.0 P1.5 P1.1Special function registers table P89LPC906 Special function registersMSB LSB Hex Special function registers table P89LPC907 CMP1 Cmpref TRIM.5 TRIM.4 TRIM.3 TRIM.2 TRIM.1 TRIM.0 WDCON# Special function registers table P89LPC908 KB2 KB6 KB5 KB4 TL0 Code Memory OrganizationData SFRLOW Speed Oscillator Option P89LPC906 Enhanced CPUClock Definitions CPU Clock OscclkWatchdog Oscillator Option Oscillator Option SELECTION- P89LPC906Clock Output P89LPC906 ON-CHIP RC Oscillator OptionCPU Clock Cclk Modification Divm Register CPU Clock Cclk Wakeup DelayBIT Symbol Function External Clock Input Option P89LPC906Low freq LOW Power Select P89LPC906High freq Med freqCPU Clocks Interrupt Arbitration Flag Bits Address Enable Bits Priority RankingInterrupt Priority Structure Summary of Interrupts P89LPC906 DescriptionTI & RI External Interrupt InputsExternal Interrupt PIN Glitch Suppression Summary of Interrupts P89LPC907,P89LPC908 DescriptionBopd EBO Rtcf Kbif Interrupts RST Port ConfigurationsQUASI-BIDIRECTIONAL Output Configuration Number of I/O Pins Available Clock Source Reset OptionPort latch data Open Drain Output ConfigurationStrong Port latch data Port pin Input data Glitch rejection INPUT-ONLY ConfigurationPUSH-PULL Output Configuration Port 0 Analog FunctionsPort Output Configuration P89LPC907 Port Output Configuration P89LPC906Port Output Configuration P89LPC908 Ports Ports TMOD.3 TmodTMOD.7 TMOD.6TAMOD.7-1 Overflows. ModeMode Tamod P89LPC907Tcon THn TFn PclkT0C/T = Overflow TLn THn TFn Interrupt T0 Pin T0C/T = OverflowPclk TL0 Timer Overflow Toggle Output P89LPC907TR0 ENT0 Pclk TH0 Timers 0 REAL-TIME Clock Source Divm Cclk FOSC2 FOSC1 FOSC0 RTCS10UCFG1.2 UCFG1.1 UCFG1.0 Cclk Frequency RTC Clock Frequency XclkExternal clock/DIVM RC Oscillator/DIVMWDT Oscillator/DIVM UndefinedChanging RTCS1-0 Reset Sources Affecting the REAL-TIME ClockREAL-TIME Clock INTERRUPT/WAKE UP Rtccon REAL-TIME CLOCK/SYSTEM Timer Brownout Detection Power Reduction Modes POWER-ON DetectionBrownout Options Power Reduction Modes Pcon Pcona Power Monitoring Functions Modes UartSFR Locations for UARTs SFR SpaceBaud Rate Generator and Selection Updating the BRGR1 and BRGR0 SfrsBreak Detect Framing ErrorBrgcon Scon Sstat More about Uart ModeSerial Port Mode 0 Double Buffering Must Be Disabled PCON.6 RB8 SMOD0 Framing Error and RI in Modes 2 and 3 with SM2 =FE and RI when SM2 = 1 in Modes 2 More about Uart Modes 2Double Buffering in Different Modes Double BufferingTransmission with and without Double Buffering 9TH BIT BIT 8 in Double Buffering Modes 1, 2Automatic Address Recognition Multiprocessor CommunicationsUart Uart Block Diagram of Reset POWER-ON Reset Code ExecutionRstsrc Comparator Configuration CIN1A CO1 CMP1 Cmpref Comparator and Power Reduction ModesInternal Reference Voltage Comparator InterruptComparator Configuration Example Analog Comparators Kbcon KbpatnKbmask Watchdog Function Watchdog timer configurationWdte Wdse Function Feed Sequence Wdcon PRE2-PRE0 P89LPC906/907/908 Watchdog Timeout ValuesControl register Watchdog Timer in Timer ModePrescaler Reset Pclk WatchdogCLK Power Down OperationWatchdog Clock Source PrescalerWatchdog Timer Watchdog Timer Dual Data Pointers Software ResetAUXR1 MOVX@DPTR, a MOVCA, @A+DPTRMove code byte relative to Dptr to the accumulator MOVXA, @DPTRIntroduction to IAP-LITE FeaturesUsing Flash AS Data Storage General DescriptionFlash Program Memory Fmcon Assembly language routine to erase/program all or part of a Accessing Additional Flash ElementsReading Additional Flash Elements ERASE-PROGRAMMING Additional Flash ElementsUCFG1 Fmadrl Conf UCFG1 User Configuration BytesP89LPC906 Unprogrammed value 00h User Security BytesSECx Address xxxxhBootstat BootvecLogical ArithmeticData Transfer Mnemonic Description Bytes Cycles Hex CodeBranching BooleanMiscellaneous RetiB8-BF D8-DF2003 Dec Initial release 104 Index Dual Data Pointers Port 0 12, 13 SFR 109 P89LPC906/907/908
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