streams?

[rougie]

Hello,

I am a <newbie> to the CCS and the PIC world. I have spent the last year in C++ and VC++, but never really dealt much with C.

So, I am rusty in C since all I was used to was, some C structures, classes, virtual functions, ADTs, Inheritance, WIN32 and its API, handlers and so forth!

At this point, I am embarassed to ask some questions, for this is why, today! I have purchased the "PICmicro MCU C: An introduction to Programming the MicroChip PIC in CCS by Nidel Gardner" handbook.

So, excuse me if my questions sound like "I need to read a book on C" type of tone! However, I am trying to catch up as most as I can.

I just got the CCS kit for the PIC16f877A micro controller a few days ago and I must say, I am full of questions!

Question#1:
I don't know about you guys but, I have looked in my C book and I have never seen the following syntax used with the colon and a number at the end of the structures member variables:

struct xxx
{ int data: 4; //I guess this sets up a default value of 4 to data?
int rw : 1;
}

What does the ": 4;" stand for?

Question #2:
I find it weird that when we want to get a character from an rs232 port we use getc() which is a built in function and when we want to get an integer we have to fetch a function called get_int() in the INPUT.C file? Why couldn't the get_int() or the get_long be part of the built in functions? I am just curious on this one! I don't mind if this is the way it is, but I would like to know if there is any patrticular reason!

Question #3:
I am not familiar with streams asides from the breif descriptions that I have read on them. I often see samples like this:

#use rs232(baud=9600, xmit=pin_c6, rcv=pin_c7,stream=HOSTPC)

what is the stream of HOSTPC and where is "HOSTPC" defined or "GPS" for that matter? I know that a stream must be a constant byte, but I just would like to know what these constants mean exactly and where can I find the full listing of available streams for my PIC.

Question#4:
I have read that pointers to functions are not allowed, however, is it okay to use the full extent of pointers as in regular C ex: an array of pointers to strings as so:

char *xxx[] = {"abc", "hij"};

or declarations of pointers to string constants as so:

char *yyy = ("abc");

Just asking?

Question #5:
I have verbally contacted CCS on this one, and I am supposed to e-mail them but I just haven't had the time yet to do so. However I will take a stab at it and see if anyone has run into this problem.

I was using the rs232 from an example in the sample booklet, when I decided to change the data bits from 8 to 7 in the serial port monitor and modified my #use rs232 to 7 bits instead of 8 as so:

#use rs232(baude=9600,xmit=PIN_C6,rcv=PIN_C7,BITS=7);

This did not work! I don't know why, If anyone knows I would appreciate their input.

Question#6:
What's a brownout!


I have so much to get used to so I will probably be back.

Thankyou all for your generous help!

This is the first time I use this sight, so I don't know how friendly the gurus of this technology are, however I hope to hear from you all!

Thanking all in advance for your feedback!

Best regards
Roberto

[PCM programmer]

[rougie]

Thankyou Avatar!

I will make note of this!

Kind regards
Robert