[sdiy] PIC help

[Scott Juskiw]

For the third time in as many years I'm making an attempt to venture  
into PIC development because all the new synth modules I want to build  
would benefit from a digital controller of some sort. I spent most of  
the weekend going over the sdiy archives and microchip website but  
sadly, am once again flummoxed by the options and am wondering if  
someone can answer a few newbie questions.

Maybe it would help if I explain my situation. My current project is a  
programmable filter bank with the following requirements:

a. 10 (at most) analogue inputs for reading pots, 10 bit ADC would be  
fine
b. a few digital inputs for reading switches and pushbuttons
c. 24 analogue outputs to control filter frequency, Q, gain etc, 12  
bit DAC would be fine
d. EEPROM for storing presets
e. ability to hook up an LCD display (2 line by 40 character or smaller)

1. What programmer/debugger do you use or recommend? I don't want to  
build one, or get some third party box. I've narrowed the choices down  
to either the PICkit 3 ($70) or MPLAB ICD3 ($220) and am wondering if  
there's any significant advantage to the ICD3 that makes it worth  
being 3X as much as the PICkit 3.

2. How do you decide which PIC chip to use? I know some of you are  
using the dsPIC33FJ128GPxxx series (Tom, Seb, Eric) and I'm more than  
happy to follow your lead, but it might be overkill for my needs. But  
they aren't too expensive, should I just go with the flow and use the  
latest and greatest chips?

3. Some of the dsPIC chips have a built-in 16-bit DAC but it appears  
to be best suited for two channels of audio, not for 24 channels of  
control voltages. Would I be better off using an external DAC to get  
24 analogue outs and avoid the internal DAC?

4. If using an external DAC, is there any advantage to using one DAC  
with lots of multiplexing to get 24 outputs vs. using several 8- 
channel DACs (e.g. TLV5610)?

5. It seems that dsPIC chips don't have enough built-in EEPROM to  
store all the info I want for the presets. Is it best to avoid trying  
to max out the internal EEPROM and use an external EEPROM? (I see that  
Seb has hooked up an EEPROM to his Digi-Mod.)

6. What do you recommend for an LCD display (2x40 character or less)  
that would be simple to hook up to a PIC? Do these things have some  
kind of common interface (SPI)?

Thanks for your help and guidance.