new to 8 pin pic

[ruijc]

Hello hoyles,

let me give you some pointers on that

For the PIC12F629/675 you have no portb, it's called GPio

So:

where you have :

TRISB = %00000000
pb0 var PORTA.0

you need to have something like:


trisio=%000001
pb0 var gpio.0

and for:

If pb0 = 1 and b0 = 0 Then one

you need to have something like:

if ( pb0=1 ) and ( b0=0 ) then one

Get the ideia?

[hoyles]

thanks ruijc,

i guess what i should have asked first was, how to access the i/o pins on the 12f629 and how to identify them as inputs or outputs.
can i assume that the 6 i/o ports will be gpio.0 thru gpio.5?
are there any pull up resistors needed for the inputs?
are there any picbasic cammands that may not be used in this pic?

thanks,
mike

[skimask]

thanks ruijc,
i guess what i should have asked first was, how to access the i/o pins on the 12f629 and how to identify them as inputs or outputs.
can i assume that the 6 i/o ports will be gpio.0 thru gpio.5?
are there any pull up resistors needed for the inputs?
are there any picbasic cammands that may not be used in this pic?
thanks,
mike

The answer to EVERY one of those questions is right in the PBP manual.

-You ask about I/O ports, there's a couple of pages in the PBP manual that have specific (to the 8 pin PIC) examples of the 8 pin PIC I/O ports and accessing them, as either inputs or outputs and setting or reading those inputs or outputs.
-You ask about pull ups? There may or may not be a section in the 12F629 datasheet about pullups.
-You have a 12 bit PIC, there's a whole section in the PBP manual on the 12 bit PIC and commands that may or may not have special needs when used with 12 bit PICs.
Tell me I'm wrong, and prove it, and I'll GIVE you every PIC I have in my desk drawer.

[hoyles]

thanks skimask,

i did not realize that there was specific info on the 8 pin pic in the manual.

that should be a great help.

thanks again,
mike

[Bruce]

Hi Mike,

Welcome to the forum. This series PIC has a 4MHz internal oscillator, an analog comparator,
and a host of other goodies you'll need the data sheet to get familiar with.

CMCON = 7 will disable the onboard comparator so you can use associated pins as digital I/O.

If you plan to use the internal oscillator, then you'll want to enable it using the INTRC_OSC
option in config. Use this below to get started. Just place the next line at the very beginning
of your program.

@ DEVICE pic12F629, INTRC_OSC_NOCLKOUT,WDT_OFF,PWRT_ON,MCLR_OFF,BOD_ON,CPD_OFF,PROTECT_OFF
DEFINE OSCCAL_1K 1' Set OSCCAL for 1k ' <-- this loads the factory calibration value for the int osc

DEFINE OSCCAL_1K 1 is in your PBP manual.

If you're curious about what all these config options are, just look in the data sheet under
the Special Features of the CPU section. You might also want to use the search feature
here to turn up even more info, but this will get you up & going for now.

I/O-pins on these are refered to as GPIO. GPIO.0, GPIO.1, etc,,.

The TRIS register is called TRISIO. TRISIO = %xxx x being 1's or 0's for inputs or outputs.

Now try something simple just to get familiar with the 12F part;

@ DEVICE pic12F629, INTRC_OSC_NOCLKOUT,WDT_OFF,PWRT_ON,MCLR_OFF,BOD_ON,CPD_OFF,PROTECT_OFF
DEFINE OSCCAL_1K 1

    CMCON = 7

loop: 
    High GPIO.0 ' Turn on LED connected to 0
    Pause 500 ' Delay for .5 seconds
    
    Low GPIO.0 ' Turn off LED connected to 0
    Pause 500 ' Delay for .5 seconds
    
    GoTo loop ' Go back to loop and blink LED forever

TIP: Just in case, you might want to first read a new 12F629 with your device programmer,
and jot down the factory calibration value. If your programmer erases this, you'll need to
know what it was.

There should be several threads around here with info on finding the proper value again, so
I won't re-type it all again here.

Use the search feature here to look around for more on using the 12F series. If you have
more questions after reading any of them, then fire away.

MeLabs has a few examples for the LAB-X4 board you might also want to have a look at;
http://www.microengineeringlabs.com/doclist.htm#X4

P.S. The 12F629 is not a 12-bit core device. It's 14-bit, so pretty much any PBP command
should work just fine with it. As long as it's not a hardware command for a peripheral that
doesn't exist on the PIC itself.

[hoyles]

thanks bruce,

that is the exact information i was looking for.

now it's time to experiment with it.

i have learned a lot over the years from your website. keep up the good work!

thanks again,

mike

[skimask]

P.S. The 12F629 is not a 12-bit core device. It's 14-bit, so pretty much any PBP command should work just fine with it. As long as it's not a hardware command for a peripheral that doesn't exist on the PIC itself.

Jeeze...I don't know how many times I've done that to myself! I've done bunches of applications with the 12Fxxx and it seems like every time, I talk myself into the fact it's a 12-bit...only to RE-figure out after a few days that it's actually a 14.
(Ok...I'll take a burger and one FOREHEAD SLAP to go...)

[Bruce]

Some of the 12Fxxx series are 12-bit core. Just not this one. In general, 12F5xx are
12-bit core, and 12F6xx are 14-bit core. The Program Memory Organization section of most
data sheets will normally indicate the core type, so it's worth a quick check if you're not
sure.