dsPIC33F, LCD, RS232, oamp,... plz help

dspic33f family reference manual

Hi, I have some problems with my project:
I use one dsPIC33f , mean that i have to work with 3.3 V supply. Now i want to interface through RS232 and work with LCD 4x16, other ICs : OAMP741,MAX232,...

1. for OAMP741, can i use +/- 5V instead +/- 9V ?

2. Can i use 3.3V to supply LCD, OAM741,... ? (if so, i only have to supply 3.3V & +/-9 V and dont need 5V ?)

3. Should i change MAX232 with MAX3232 instead (cause Max3232 works with 3.3V)
For RS232 connection, the capacitors use for MAX232/MAX3232 should be 1uF or 10uF,... is the best?
And in the datasheet of max3232/max232 , they use one cap 0.1up as bypass function. That mean they use total 5 caps. In some sources, they use only 4 caps??

4. I use dsPIC33FJ256MC710 (a bit troublesome , cause i'm very new at it). Which is the best OSC for this dsPIC (20Mhz / 40Mhz / 80Mhz .. . )?. I read the datasheet of dsPic family and cant really understand the use of PLL to multiple OSC... It says that at Fosc=80Mhz then the calculating rate could be maximum = 40MIPs .

5. then the last purpose is to display the temperature of a heat-exchange and send data to a PC. How can i reduce the disturbances to the AD convert? One of my friend used Caps 104pF & Registors to filter the analog signal at input pin. is that ok ?

:|:|

dspic33 lcd

1. RTFM
2. RTFM
3. yes - you should change to MAX3232 and use 4 charge capacitors 100n and one bypass cap on the voltage supply pin - 100n also. this caps cost almost nothing so don't try to find what will happen if you omit some of them.
4. the best osc is the one you need... RTFM. the oscillation frequency HAS to be divided by two, as this chip uses two clock cycles for one instruction cycle. so 80MHz output freq will give you an 40MIPS operation. there are some other rules for the PLL multiplier, so RTFM. I use 25MHz quartz oscillator to obtain 40MIPS in the following way:
1. FIN is divided by 5 => 5MHz at the input of PLL.
2. then it is multiplied 32 times which gives 160MHz on the output of PLL loop
3. the PLL output has to be further divided by 2, which gives output frequency 80MHz
4. ... which results in 40MIPS operation

in the Family Reference Manual there are examples of PLL configurations with great detail,,, just read it...

5. yes you can filter it a bit.

0x41 0x56 0x45!!

dspic33 lcd interface

thanks for advices !
But, RTFM ?? Does this mean .... :!: ?

dspic33f 80mhz

how to program dsPIC33F , i mean from where i can get programmer

Added after 36 seconds:

how pic is programmed using JTAG