learn 8085_ pin description

8/12/2019 Learn 8085_ Pin Description

1/4

STIRI ROMANE

ASCII

ASCII

ASCII

ASCII ENGINE

BLOG ARCHIVE

Pin Description

Shiriki 0 Mengineyo Blogu Ifuatayo
http://www.blogger.com/https://www.blogger.com/next-blog?navBar=true&blogID=5913854448534801152http://i8085.blogspot.com/p/pin-description.htmlhttp://atat.ro/


2/4

5/7/2014 Learn 8085: Pin Description

http://i8085.blogspot.com/p/pin-description.html 2/4

that the microprocessor is reset. This signal is used

to reset other devices in system.

4 SOD Serial Output Data.

This is an active high, serial output port pin, used to

transfer serial 1 bit data under software control.

5 SID Serial Input Data.

This is an active high, serial input port pin, used toaccept serial 1 bit data under software control.

6 TRAP This is a non-maskable interrupt and has highest

priority.

7 RST 7.5 Pin 7-9 are vectored interrupt that transfer the

program control to specific memory location. They

have higher priority than the INTR interrupt.

8 RST 6.5

9 RST 5.5

10 INTR Interrupt request. General purpose interrupt.

11 INTA Interrupt acknowledgement. This is used to

acknowledge interrupt.

12-19 AD0-AD7 These pins are multiplexed to be used as address bus

as well as data bus.These are signal lines which are

bidirectional & they serve dual purpose. They are

used as lower order address bus as well as data bus.

20 VSS It is ground reference.

21-28 A8-A15 These 8 signal lines are unidirectional and used for

most significant bits called higher order address bus

of a 16-bit address.

29,33 S0 These are status signal, similar to IO/M, can

identify various operations.

IO/M S1 S0 Machine Cycle

0 1 1 Opcode fetch

0 1 0 Memory read0 0 1 Memory write

1 1 0 I/O Read

1 0 1 I/O Write

1 1 1 Interrupt

Acknowledgement

30 ALE Address Latch Enable

ALE signal is used to separate AD0-AD7ie

demultiplex

ALE=1 indicates that contents are address.

ALE=0 indicates that the contents are data.

31 WR (active low) Write. This is a Write control signal (active low).

This signal indicates that the data on the data bus are

2012(1)

2011(7)

10/09 - 10/16(5)

To find factoria

To multiply two

How to add twowithout usingcommand?

8085 Architectu

How to count nua byte?

10/02 - 10/09(1)

09/25 - 10/02(1)
http://i8085.blogspot.com/2011_09_25_archive.htmlhttp://void%280%29/http://i8085.blogspot.com/2011_10_02_archive.htmlhttp://void%280%29/http://i8085.blogspot.com/2011/10/how-to-count-number-of-1s-in-byte.htmlhttp://i8085.blogspot.com/2011/10/8085-architecture.htmlhttp://i8085.blogspot.com/2011/10/how-to-add-two-numbers-without-using.htmlhttp://i8085.blogspot.com/2011/10/to-multiply-two-numbers.htmlhttp://i8085.blogspot.com/2011/10/to-find-factorial-of-number.htmlhttp://i8085.blogspot.com/2011_10_09_archive.htmlhttp://void%280%29/http://i8085.blogspot.com/search?updated-min=2011-01-01T00:00:00%2B05:30&updated-max=2012-01-01T00:00:00%2B05:30&max-results=7http://void%280%29/http://i8085.blogspot.com/search?updated-min=2012-01-01T00:00:00%2B05:30&updated-max=2013-01-01T00:00:00%2B05:30&max-results=1http://void%280%29/


3/4



to be written into selected memory or I/O location.

32 RD (active low) Read. This is a Read control signal (active low). This

signal indicates that the selected I/O or memory

device is to be read and data are available on data

bus.

34 IO/M This is a status signal used to differentiate between

I/O and memory location. When it is high. It indicatesan I/O operation; when it is low, it indicates a

memory operation.

35 READY If the signal at READY pin is low, the

microprocessor enters in to wait state. This signal is

primarily used to synchronize s lower peripherals with

the microprocessor.

36 RESET IN When the reset pin is activated by an external key all

the internal operations are suspended and the

program counter is cleared and the program

execution begins at zero memory address.

37 CLK OUT Clock Output.

This signal can be used as the system clock for other

devices.

38 HLDA Hold acknowledgement. This pin is used for hold

acknowledgement.

39 HOLD When HOLD pin is activated by an external signal

the microprocessor relinquishes control of buses and

allows the external pheripheral to use them.

40 VCC +5V power supply.

Recommend this on Google
http://www.blogger.com/share-post.g?blogID=5913854448534801152&pageID=2723880653233551693&target=pinteresthttp://www.blogger.com/share-post.g?blogID=5913854448534801152&pageID=2723880653233551693&target=facebookhttp://www.blogger.com/share-post.g?blogID=5913854448534801152&pageID=2723880653233551693&target=twitterhttp://www.blogger.com/share-post.g?blogID=5913854448534801152&pageID=2723880653233551693&target=bloghttp://www.blogger.com/share-post.g?blogID=5913854448534801152&pageID=2723880653233551693&target=email


4/4



Home

Subscribe to: Posts (Atom)

funny quotes

I hear voices in my head and they don't like you.

Edward Cullen

CHEEKY QUOTES

TOTAL PAGEVIEWS

1 3 4 4 8Priyatam

View my complete profile

ABOUT ME

Join this site

w ith Google Friend Connect

Members (3)

Already a member? Sign in

FOLLOWERS

Picture Window template. Te mplate images by ranplett. Po wered by Blogger.
http://www.blogger.com/http://www.istockphoto.com/googleimages.php?id=6250315&platform=blogger&langregion=en_GBhttp://www.blogger.com/profile/10525108239438367510http://www.blogger.com/profile/10525108239438367510http://twitter.com/home?status=I%20hear%20voices%20in%20my%20head%20and%20they%20don%27t%20like%20you.%20~%20Edward%20Cullen%20www.CheekyQuotes.com%20funny%20quoteshttp://www.cheekyquotes.com/http://i8085.blogspot.com/feeds/posts/defaulthttp://i8085.blogspot.com/

learn 8085_ pin description

Documents