16F877 out of RAM/ROM => suggestions for new PIC??

[weg22]

Hi all,

I'm pretty much maxed out in terms of RAM/ROM for my PIC16F877A (8K/368). I could just go to Microchip's web site and select a PIC with more memory, but I was hoping people could suggest a few to help narrow down my search. I have the PIC16F877A in 40-pin PDIP form and I want to use the same package (i.e. I'm hoping to get something that's interchangeable).

I noticed there's a PIC18F4680 with 32K/3328 which would be more than enough. Has anyone had any problems with this PIC?

Thanks!

[treitmey]

Give us an idea what the scope of the project is.
LCD,Servo,Motor,DtoA,AtoD,wireless,USB,keypad,modem,..?

[weg22]

Well, I will be controlling several servos as well as reading in data from a GPS unit (RS232) and Inertial Measurment Sensor (RS232). Also, I will need to use inverse trig functions such as atan2. I will be using interrupts such as:

INT_RDA: read in data from GPS device
INT_CCP: read the length of a PWM pulse (servo)
INT_TIMER0: generate PWM pulse

[treitmey]

I went to microchip and went to 18F4525 and down from there looking at
chips with 2-uart. anyone have a preference, run any of the following..
18F6622
18F6627

18F8527
18F8622

From here look at the pin out/prices/ect. AND MOST DEFINATLY the errata sheets. Some silicon have lots of errors.

[weg22]

I don't think the ones you suggested are 40-pin PDIP. The 2nd UART is not a requirement. I will be pinging the IMU when I want data so I know when it will be coming in. I can wait for it...

I guess I will just go with the 18F4680 unless anyone has had trouble with this chip previously?

Thanks

[treitmey]

If 1 UART will do, I am very happy with the 18F4525. 40Pin dip with some motor controls.
For my 2 cents. I will allways use seperate hardware usarts for 2 serial streams, for anything short of debuging.