IBM EM78P447N manual I/O Ports, Iod

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EM78P447N

8-Bit Microcontroller with OTP ROM

4.4 I/O Ports

The I/O registers, Port 5, Port 6, and Port 7, are bi-directional tri-state I/O ports. The functions of Pull-high, R-option, and Open-drain can be performed internally by CONT and IOCE respectively. There is input status change wake-up function on Port 6, P74, and P75. Each I/O pin can be defined as "input" or "output" pin by the I/O control register (IOC5 ~ IOC7). The I/O registers and I/O control registers are both readable and writable. The I/O interface circuits for Port 5, Port 6, and Port 7 are shown in Figures. 7(a) and (b) respectively.

PORT

		PCRD
	Q	PR	D
	Q	CLK		PCWR
	Q	CL
	Q	PR	D
			D	PDWR
	Q	CLK		PDWR
	Q	CL
0	M			PDRD
1	U
1	X

IOD

Fig. 7 (a) The I/O Port and I/O Control Register Circuit

VCC ROC

Weakly

Pull- up

PORT

Rex*

PCRD

Q PR D

CLK

Q CL

Q PR D

CLK

Q CL

0 M U 1 X

PCWR

IOD

PDWR

PDRD

*The Rex is 430K ohm external resistor

Fig.7 (b) The I/O Port with R-Option (P70, P71) Circuit

16 •	Product Specification (V1.1) 03.30.2005

(This specification is subject to change without further notice)

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Contents EM78P447N Elan Microelectronics Corporation Contents Specification Revision History General Description EM78P447NBWM PIN Assignment EM78P447NAS Pin Description Symbol Pin No Type FunctionEM78P447NAP and EM78P447NAM Pin Description EM78P447NCK and EN78P447NCM Pin Description Power supplyEM78P447NBP and EM78P447NBWM Pin Description Function Description EM78P447NDK and EM78P447NDM Pin DescriptionOperational Registers 1 R0 Indirect Addressing Register2 R1 Time Clock /Counter 3 R2 Program Counter & StackCall RET Retl Reti FffhData Memory Configuration 5 R4 RAM Select Register 6 R5~R7 Port 5 ~ Port77 R8~R1F and R20~R3E General Purpose Register R5, R6 and R7 are I/O registersSpecial Purpose Registers 8 R3F Interrupt Status RegisterAccumulator Control Register3 IOC5 ~ IOC7 I/O Port Control Register Iocb Wake-up Control Register for Port6TCC Rate WDT RateIoce WDT Control Register WUEIocf Interrupt Mask Register ExieTCC and WDT Block Diagram TCC/WDT & PrescalerI/O Ports IODReset and Wake-up ResetUsage of Sleep1 and Sleep2 Mode SLEEP2 SLEEP1Address Name Reset Type Bit Summary of the Initialized Values for RegistersR3FISR Exif TcifWUE7 WUE6 WUE5 WUE4 IocbPrevious status before reset Previous value before resetStatus of RST, T, and P of Status Register Events that may Affect the T and P StatusController Reset Block Diagram InterruptMode OscillatorOscillator Modes Crystal Oscillator/Ceramic ResonatorsXTAL Summary of Maximum Operating SpeedsConditions Fxt max.MHzExternal RC Oscillator Mode Oscillator Type Frequency Mode C1pF C2pFHXT LXTCode Option Register Code Option Register WordPR2~PR0 are protect bits, protect type as following ProtectPower On Considerations External Power On Reset CircuitCustomer ID Register Word Bit 12~0 Customer’s ID codeReset Residue-Voltage ProtectionInstruction Set NOP DAAContw SlepDjza R DJZ RRrca R RRC RTiming Diagram AC Test Input/Output W aveformDC Electrical Characteristic Symbol Parameter Condition Min Typ Max UnitTa= 25 C, VDD= 5.0V±5%, VSS= Items RatingTa=- -40 C ~ 85 C, VDD=5V ±5%, VSS=0V AC Electrical CharacteristicSymbol Parameter Conditions Min Typ Max Unit Device characteristic Vih, Vil of TCC, /INT, /RESET PinPort5, Port6 Port7 Voh vs. Ioh,VDD=5V Port5, Port6, and Port7 Voh vs. Ioh, VDD=3V Vol/Iol VDD=5V Vol/Iol VDD=3V Vol/Iol 100 Vol/Iol WDT Cext=100pF, Typical RC OSC Frequency Typical ICC1 and ICC2 vs. Temperature Maximum ICC1 and ICC2 vs. Temperature Typical ISB1 and ISB2 vs. Temperature Maximum ISB1 and ISB2 vs. Temperature EM78P447N HXT ImA Lead plastic dual inline package（DIP）－ 300 mil Package Type Pin Count Package SizeLead plastic dual inline skinny package（DIP）－ 300 mil Lead plastic dual inline package（DIP）－ 600 mil838 27TYP EM78P447N