Example code for 74hc595

azmax100

hi

Can sombody show me some example with shiftout from BS2 to 74hc595.

I want to use·2 of ·74hc595 to drive some relay (about 16 of them)·trough 2 of uln2803.

I've view the example in Stampworks manual but it's too brief for me to understand.

I dont need full code just some example so i can learn·from it.

Thanks & regards·

Newzed

Hereis a 595 Test Code.



Sid

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Yesterday is history, tomorrow is a mystery, and today is a gift.

That is why they call it the present.

Don't have VGA?
Newzed@aol.com

Chris Savage

Hello,

The Stamp Works Manual has examples connecting one or more 74HC595 chips. You can find the manual and downloadable source code on the following page. Take care.

http://www.parallax.com/detail.asp?product_id=27297

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Chris Savage
Parallax Tech Support

azmax100

hi.

Thanks Newzed for the example.

[noparse][[/noparse]'Now suppose we want to make pins Qa, Qb, Qd and Qh all high to turn on 4 Darlingtons
'at once.· We are using lsbfirst, so the first bit out goes to Qh and the last bit
'out goes to Qa.· In binary, we would want to send %11010001.· However, you can use
'either binary or decimal - it doesn't matter.· After all, the decimal gets converted
'to binary by the Stamp before it is transmitted.· So %11010001 = 128+64+16+1=209


LOW latch
SHIFTOUT dat, clk, LSBFIRST, [noparse][[/noparse]209]
PULSOUT latch, 5
LOW latch
'The four outputs pins will stay high until you turn them off or power down
GOTO start]

Now I understand better but how to make the pin low. let say i want to make pin Qb high for 100us can I do this?

LOW latch
SHIFTOUT dat, clk, LSBFIRST, % 01000000
PULSOUT latch, 5
PAUSE 100
LOW latch

Is it right? Sorry for dumb question. I'm a self learner.

Chris thanks for the link. actually I already read it but not quite understand cause it's too brief.

·

Newzed

Asmax, in the shiftout 209 example the pins will be HIGH.· My error.· Your example to make Qb HIGH is correct.· To make any pin
LOW, simply send a 0 to that pin.

Sid

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Yesterday is history, tomorrow is a mystery, and today is a gift.

That is why they call it the present.

Don't have VGA?
Newzed@aol.com
·

azmax100

Hi all.

Thanks newzed.

To make the output high send %1

to make the output low send %0

That simple. How come I did't think of that.