Which chip? New to this stuff

[Thorpydo]

Hey

I'm pretty new with this stuff. Ive been using the basic stamp for a project of mine. I'd like to work with a pic..

I need a very few amount of pins, 6 would be fine. I believe that I also need EEPROM (Is that 'RAM' on microchips site?). Is there anything else to base my decision of what chip I get on? Will I need a crystal, or is there one built into the chip?

Im going to be programming it in basic, what are some available compilers?

Anything else that may help me out?

THANKS!

 

[Oznog]

I started with 28 pin DIP pkg PIC18F252 & 40 pin PIC18F452, Warp13 programmer, and CadSoftUSA's HiTech C compiler. Never used BASIC. The 18F's fast, lots of memory, quite powerful. It uses a larger instruction set oriented towards compilers.

The "Words" is nonvolatile program memory on Microchip's selection guide. Once the code is programmed, it will stay safe until reprogrammed. "Bytes" is volatile RAM space available to the program- unlike some architectures, instruction code space and RAM is not interchangeable. Yes, it is quite possible to run out of RAM space. "EEPROM" is nonvolative memory that the code can write/read from which will remain stored through resets and loss of power. It's slow and you don't use it unless you need the nonvolatile capabilities.

Get "Flash" memory type ("F" in the name). The "C" types require UV to erase, or may be unerasable, or "OTP" which means the program is stored in an off-the-part EEPROM.

Some PICs can operate off internal oscillators. The frequency options are limited. Most parts use crystals, but this isn't difficult to make work.

PIC18F877, 16F628, 16F84 are all very popular. Be sure to check the errata sheets on other parts- the 18F1320 was shown at 40MHz, but the spec sheet revealed the current revision may not fetch reliably over 4MHZ!

 

[Thorpydo]

Ok, that helps.

I don't understand why I would anything super fast or with a large memory capacity.

I was looking at the PIC12F629.. Seems like anything more would be overkill. Does that sound good?

Heres the program I'm going to be running.

'{$STAMP BS1}
'{$PORT COM1}

DIRS=00001010'input/output
PINS=00000010'high/low

SYMBOL Trigger=PIN0 'INPUT
SYMBOL Emitter=PIN1 'OUTPUT
SYMBOL Detector=PIN2 'INPUT
SYMBOL Solenoid=PIN3 'OUTPUT

SYMBOL Dwell=B4
SYMBOL Drop=B5

LET dwell=1000
LET drop=400



ReadyLOOP:
BUTTON Trigger,0,255,0,B1,0,ReadyLOOP

HIGH 3 'Activates Solenoid

DetectorLOOP:
BUTTON Detector,1,255,0,B2,0,DetectorLOOP

PAUSE Dwell
LOW 1 'Deactivates Solenoid
PAUSE Drop

DepressLOOP:
BUTTON Trigger,1,255,0,B3,0,DepressLOOP

GOTO ReadyLOOP

 

[Oznog]

It's $6.19 vs $1.68 at Digikey, but the part cost isn't an issue unless you buy a lot of them.

Myself, I sure can use up counters, PWMs, ADCs, external interrupts, I2C, memory, and pins fast. I like to keep my options open.

I like having good C support with the HTSoft PICC-18 compiler. I looked at their PIC16 products and their design environment was ancient, didn't support all the chips either.

Actually I do want to program for the PIC12 & PIC16 series, primarily because I often want to make stuff a lot smaller.

 

[ezuk]

Tibbo?

Tibbo have some interesting products for this. If you used the basic stamp, it might be a nice step up.

They've got BASIC-programmable stuff... with an IDE on the computer. https://www.tibbo.com/taiko.php

Maybe that's what you need?

 

[blueroomelectronics]

Wow why did you dig up such an ancient thread? And they have no 8 pin devices like the PICAXE (step sideways)

 

[ezuk]

Wow why did you dig up such an ancient thread? And they have no 8 pin devices like the PICAXE (step sideways)

Wow, that's weird. Sorry about the ancient thread -- for some reason it showed up on my front page.