PIC Questions

[Sandy]

The PIC is a very simple RISC processor that is good for lots of control type
of applications (lots of other things to). They are inexpensive, and the tools
are low cost. Lots of I/O depending on the model. Limitations in my mind are
memory and not having a traditional 'Bus'. The bad also makes them very good
for smaller projects. The HC11 is a more traditional CPU, lots of I/O easy to
add boat loads of memory, but has the added expense of having too! PIC's are
finding their way into everything, and seem like easy to gets started. The PIC
and HC11 boards are pretty plentyful, with a bit lower cost to the PIC. The
choice would have to be based on cost, size, and how much memory. Their are
lots of addon's for the PIC, but they sort of defeat the simpicity of it.
So my
choice would be base on can I do it with just the PIC by itself, if I have to
get a bunch of special addons' I would go with the HC11. Both have similar on
chip functionality, I think the HC11 has some more advanced subsystems
available, supports interrupts, can run a rtos, etc.

2 Cent...


Sandy

At 05:57 PM 11/3/98 -0500, you wrote:
>For us novices, could you briefly explain what a PIC is exactly and describe
>(manufacturer / model / part#) the board you mention.  Also a brief
>explanation of why you would prefer the PIC board to the HC11 (assuming you
>could find an HC11 board).
>
>Thanks
>
>Rick
>
>> -----Original Message-----
>> From: Orin Eman [SMTP:orin at WOLFENET.com]
>> Sent: Tuesday, November 03, 1998 3:20 AM
>> To: diy_efi at efi332.eng.ohio-state.edu
>> Subject: Re: PIC Questions
>> 
>> 
>> > Was looking at the HC11' but the PIC is lower cost and easier to get.
>> Just
>> > not needing the power of the HC11, just the i/o. Seems that several
>> PIC's
>> > have the same I/O capability so that makes is easy.
>> 
>> I've looked at HC11 vs PIC too... kept coming back to the PIC.
>> I also looked at the PIC with more IO vs one with less IO with
>> some latches... the bigger PIC won easily (pin count!).  I have a PIC16C73
>> based data aquisition board... drives a character LCD and RS232.
>> I _didn't_ use the on-board AtoD, but used a Motorola 145051 10 bit
>> chip instead.  I had to do the serial by hand (but the assembler
>> macro capability is good - I should post the code).  Used the
>> interrupt on change inputs to aquire ignition timing - interesting
>> since this feature is buggy on the 16C73.  Picked up a couple
>> of duty cycles using the capture inputs...
>> 
>> Orin.
>