pic16f84a 4x3 keypad interfacing

[khgsm2007]

hi Nigel and all
iam trying to insert a 3x4 keypad on pic16f84a project,

1. as afirst step i try to simulate Nigel Tutorial 9.3 and make needed changes on the asm file to change pic628 with pic16f84a

2. unfortunally the hardware assigned for this tuorial is very confusing , it connect rows 4...1 to RB0...RB3 , while in the code RB0...RB3 assumed as inputs also RB4...RB7 asumed as outputs , while they are connected to Columns which supposed to be inputs with pull up resistor,


Iam using protus simulator to simulate this toutrial but i get uncorrect data about the pressed key or some times nothing at all..

your comment on these notes will higly appriciated

best regards

 

[Nigel Goodwin]

Built it and see how it works (which it does), don't play with simulators.

 

[BeeBop]

Built it and see how it works (which it does), don't play with simulators.

This is good advice (well except for the typo = build)

So many starters get seduced by simulators....

Get in the real world man!

 

[ericgibbs]

This is good advice (well except for the typo = build)

So many starters get seduced by simulators....

Get in the real world man!

hi BeeBop,

seduced by simulators ,we should be so lucky.
[I dont think they have quite perfected that model yet.]

Simulators have their place like any other 'tool'.

Many projects rely heavily on simulation.
From training bulk tanker captains to astronauts and pilots.

The big advantage I have found in using simulators in my work is.

If they dont work in simulation, there's a 99% chance it will not work on site.
Having said that, even if it works in simulation it may well not work on site.

But it certainly reduces the odds of failure, by a big factor.

 

[BeeBop]

hi BeeBop,

seduced by simulators ,we should be so lucky.
[I dont think they have quite perfected that model yet.]

Simulators have their place like any other 'tool'.

Many projects rely heavily on simulation.
From training bulk tanker captains to astronauts and pilots.

The big advantage I have found in using simulators in my work is.

If they dont work in simulation, there's a 99% chance it will not work on site.
Having said that, even if it works in simulation it may well not work on site.

But it certainly reduces the odds of failure, by a big factor.

Hi Eric,

Sorry Eric, didn't mean to dis the simulator. It isn't that I have anything against simulators, but they are tools, and tools do require you learn how to use them...
especially with things like micro controller inputs...

I've seen so many instances of this tool misused, when in so many cases doing the same by hardware would be so simple...

As for Nigel's tutorials, I find them quite clear and easy to follow.

As for simulators, I like flight sims.

 

[khgsm2007]

RE:

Dears
whats wrong with simulators ??!! , I agree that it is not nessesary for
a successful simulation there will asuccess practical model
But for 100% sure a simple model (pic16f84 keypad )will not work if it is not passed the software simultion .

what iam asking is that for the 9.3 toutrial when swaping the 4 rows positions
on pic16f84 with the 3 columns positions i get random stuff of pressed keys ,

i wonder if there any hints rather than just dont using simulators


best regards

 

[Nigel Goodwin]

Dears
whats wrong with simulators ??!! , I agree that it is not nessesary for
a successful simulation there will asuccess practical model
But for 100% sure a simple model (pic16f84 keypad )will not work if it is not passed the software simultion .

what iam asking is that for the 9.3 toutrial when swaping the 4 rows positions
on pic16f84 with the 3 columns positions i get random stuff of pressed keys ,

i wonder if there any hints rather than just dont using simulators

The tutorial works perfectly, so your problem is the simulator, or how you've used it.

 

[bigal_scorpio]

Hi guys,

I'm just wondering if the OP is having problems with Nigels (excellent) code, because he is using it on a 84 in the simulator, or is it an 84A (he mentions both) could be causing problems with A to no A, I've been there!

I would be trying Nigels code in the simulator with the original PIC that Nigel used, I'm sure that would work, and THEN worry about migrating to whichever PIC he has.

Regards..............Al

PS have you finished painting altogether yet Eric?

 

[ericgibbs]

Hi guys,

I'm just wondering if the OP is having problems with Nigels (excellent) code, because he is using it on a 84 in the simulator, or is it an 84A (he mentions both) could be causing problems with A to no A, I've been there!

I would be trying Nigels code in the simulator with the original PIC that Nigel used, I'm sure that would work, and THEN worry about migrating to whichever PIC he has.

Regards..............Al

PS have you finished painting altogether yet Eric?

hi,
I agree that the OP should prove his ideas in the sim using the original PIC.

Not quite finished the outside, missed the last 3 days sunshine due to a bad head cold thats going around.

I'm expecting to see you on the 'Antiques Road Show' TV program anytime now with all that old kit you keep
pulling out of that bits box of yours.

 

[bigal_scorpio]

hi,
I agree that the OP should prove his ideas in the sim using the original PIC.

Not quite finished the outside, missed the last 3 days sunshine due to a bad head cold thats going around.

I'm expecting to see you on the 'Antiques Road Show' TV program anytime now with all that old kit you keep
pulling out of that bits box of yours.

Hi Eric,

I'm typing at a distance, don't want to catch your cold! hehehe

Seriously we all had it about a month ago, it was a bugger!

Speaking of the antiques, I just rediscovered a windowed pic 16C71 but don't think my programmer will do them, the new one anyway!

The wife just bought me an EasyPic5 board and its ace, can't understand all it does yet but by god its fast at programming. Trouble is I now need to learn MeBasic as the debugger part only works with that.

Still no thoughts on how to do the car seats but I have now acquired some Rotary Encoders from Ebay, but understanding them is another matter, grey code indeed, its all grey to me!

Regards...........Al