I/O Ports, Iod | IBM EM78P447N manual

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)

Image 20

IBM EM78P447N manual I/O Ports, Iod

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 Description Operational Registers 1 R0 Indirect Addressing Register2 R1 Time Clock /Counter 3 R2 Program Counter & Stack Call RET Retl Reti Fffh Data 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 registers Special Purpose Registers 8 R3F Interrupt Status RegisterAccumulator Control Register 3 IOC5 ~ IOC7 I/O Port Control Register Iocb Wake-up Control Register for Port6TCC Rate WDT Rate Ioce WDT Control Register WUE Iocf Interrupt Mask Register Exie TCC and WDT Block Diagram TCC/WDT & Prescaler I/O Ports IOD Reset and Wake-up Reset Usage of Sleep1 and Sleep2 Mode SLEEP2 SLEEP1 Address Name Reset Type Bit Summary of the Initialized Values for Registers R3FISR Exif TcifWUE7 WUE6 WUE5 WUE4 Iocb Previous status before reset Previous value before resetStatus of RST, T, and P of Status Register Events that may Affect the T and P Status Controller Reset Block Diagram Interrupt Mode OscillatorOscillator Modes Crystal Oscillator/Ceramic ResonatorsXTAL Summary of Maximum Operating SpeedsConditions Fxt max.MHz External RC Oscillator Mode Oscillator Type Frequency Mode C1pF C2pFHXT LXT Code Option Register Code Option Register Word PR2~PR0 are protect bits, protect type as following Protect Power On Considerations External Power On Reset CircuitCustomer ID Register Word Bit 12~0 Customer’s ID code Reset Residue-Voltage Protection Instruction Set NOP DAAContw Slep Djza R DJZ RRrca R RRC R Timing Diagram AC Test Input/Output W aveform DC Electrical Characteristic Symbol Parameter Condition Min Typ Max UnitTa= 25 C, VDD= 5.0V±5%, VSS= Items Rating Ta=- -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 Pin Port5, 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 Size Lead plastic dual inline skinny package（DIP）－ 300 mil Lead plastic dual inline package（DIP）－ 600 mil 838 27TYP EM78P447N