PIC 16F and PIC 18F microcontrollers

[simrantogether]

Hi,

I wanted to see as how PIC 18 F series is better than pic 16 F apart from that it does 16 bit processing rather than 8 bit.


i.e. what tasks can be done at pic 18F that cannot be done at PIC 16F...

Regards,

Simran..

 

[futz]

I wanted to see as how PIC 18 F series is better than pic 16 F apart from that it does 16 bit processing rather than 8 bit.

The 18F series are still 8-bit processors. They're no more 16-bit than the 16F's.

i.e. what tasks can be done at pic 18F that cannot be done at PIC 16F...

Nothing really. They're just improved designs and they're somewhat easier to write code for. And I guess the chips are better designed for running C executables (not that I care - I love assembly).

 

[blueroomelectronics]

I was tinkering with the dsPIC30F3012, now that's some PIC and can run at 30MIPs. 16 bit too and all in a tiny 18pin PIC.

 

[futz]

I was tinkering with the dsPIC30F3012, now that's some PIC and can run at 30MIPs. 16 bit too and all in a tiny 18pin PIC.

I'm putting together a Digikey order with a couple of those 16-bit chips (and other stuff). It'll be interesting to see Microchip's take on a bigger MCU.

 

[kchriste]

The 18F series have more instructions than the 16F. The multiply, compare, conditional branch, MOVFF and table instructions make programming less tedious. Oh, and they also have the "access bit" which eliminates a lot of bank switching. Do a lot with the 16f series still, but the 18f makes it easier from an assembly language point of view.

 

[Krumlink]

I am using the 18F series chip in C, and I love it. It makes more sense than assembler (to me) so it may be the direction you wight want to go in.

 

[simrantogether]

Hi...

Hi,

Will it be good to say that We follow pic 18 because they are easy to program in assembly and secondly that they have more features.

Regards,

Simran..

 

[futz]

I am using the 18F series chip in C, and I love it. It makes more sense than assembler (to me) so it may be the direction you wight want to go in.

That's fine, but C looks the same whether you're programming for 16F or 18F. The "easier to program" bit refers to assembly language and to how the chip is designed to be better for C compilers to work with. It doesn't mean writing C code is any different.

 

[kchriste]

Yes, and MicroChip also has a free C compiler for the 18F series but no free one for 16F. Also, the 18F is better optimized for C as Futz has mentioned.

 

[simrantogether]

Yes, and MicroChip also has a free C compiler for the 18F series but no free one for 16F. Also, the 18F is better optimized for C as Futz has mentioned.

It seems that 18f series processor is designed specially for easy programming , more features and C compatibility...

Regards,

Simran..

 

[atferrari]

If you follow a line of micros along the time, is quite possible that the latest will seem "easier" than previous. With PIC is basically like this.

If you are starting with them go for the 18F or higher. I use Assembly and they are simpler to use than the 16F.

What comes to my mind right now:

multiplication 8 x 8 in one instruction
any register can copy data to any other one
fast saving of the environment variables upon interurpts (limited)

Not tried the 24F or 30F yet.

 

[justDIY]

if clock accuracy isn't a big deal, many of the 18F let you combine the internal 8mhz rc with the 4x pll ... 32mhz clock speed with no external crystal or caps.

 

[skyhawk]

It really depends on your needs and what you are trying to do. If all you are doing is blinking some leds, it doesn't matter much. An humble 10F200 can handle 6 leds by charlieplexing and a 12F508 can handle 20 leds. I've build an LCD signboard using a lowly 16F54 ($.55 US from Newark). The basic message software takes a bit over 100 instructions out out of the available 512 lines. There's room for 6-10 more messages. Yes, programming can be a pain with only a two-level stack, but it's also fun. Mid-level pics add more features such as interupts, deeper stack, and more timers and other peripherals. 18F add still more features including hardware multiply and a faster clock. While the 16F running at 5 MIPS can only do crude video, a 30F at 30 MIPS becomes interesting for video. I am currently interested in what a 30F or 24F can do with computationally intensive problems such as guidance, navigation, and control.

 

[donniedj]

Microchip has the good fortune to continually progress and improve. F84 got upgraded, F87x got upgraded, and so to has the 16F and 18F. Each improvement is just a new part number. So yes, 18F is better from the 16F in every way by design. There not to be compared because its just a continuation of motion. You cannot compare a small snow ball that traveled down 10 from the same now large snow ball that traveled down 50 feet, for its the same snow ball but seen at a different point in time.