Pic18F452

[GrandPa]

Mister e, you said

"ADC_CLOCK 2 refer to ADCS1:ADCS0 bits (ADCON0<7:6>)"

I would like to know where I can find information about this. Or ,maybe easier, can you explain how ADC_CLOCK is "translated" to Focs/32. Is this simply the decimal value of ADCS1:ADCS0 bits?

Thanks!

[Melanie]

GrandPa...

"ADC_CLOCK 2 refer to ADCS1:ADCS0 bits (ADCON0<7:6>)"

I would like to know where I can find information about this

You can find the information you seek and it's all explained in great detail in the DATASHEET for the PIC you are using. Download it from www.microchip.com and study...

Tip: NEVER program a PIC without first studying it's Datasheet.

evilpic...

No, you're not asking too much, but this is very basic stuff that you should be capable of figuring for yourself.

Take a look at the LCDOUT command located here... http://www.melabs.com/resources/pbpmanual/

Scroll down until you find the DEFINE statements and change them accordingly for your preferred hardware connections.

Tip: NEVER program anything without first studying the compiler manual.

[GrandPa]

Thank's Melanie, but I've actually read the datasheet and use it currently. I'm actually setting the ADCON0 register directly instead if using the define.

My question is very specific about the DEFINE ADC_CLOCK.
What I don't understand is the meaning of the parameter (number) after the define:

In the book you have :
DEFINE ADC_CLOCK 3 'ADC clock source (rc = 3)
WHY does 3 mean RC clock ?

And

Mister e wrote:
DEFINE ADC_CLOCK 2 ' ADC clock source (Fosc/32)
Why does 2 mean Fosc/32

After reading the datasheet, I came to the conclusion that this number is the binary values of ADCS0:ADCS2 (PIC18F4620 here). But I wanted to make sure. So let me ask again:

----> Is this the decimal value of ADCS0:ADCS2 ?


(btw: I'm french, trying my best to explain my question)

J-P

[Melanie]

Yes, whatever you set in DEFINE ADC_CLOCK n, where 'n' is a number between 0 and 7 will reflect in bits ADCS2:ADCS1:ADCS0 as per the table in the PICs DATASHEET that I refered you to..

If you set a number greater than 7, then only the lowest three bits of your define will be used... ie DEFINE ADC_CLOCK 8 will set ADCS2=0,ADCS1=0 and ADCS0=0.

I will add, that if you don't specify a DEFINE ADC_CLOCK in your program, the default value if you use ADCIN will be 3 (ie ADCS2=0, ADCS1=1, ADCS0=1).

[evilpic]

I really need to comunicate a LCD serially with the computer, i'm using the windows hyperterminal to send characters through the RS232 and a MAX232 driver circuit included on my PIC trainer, this is the code i'm using to display those characters on the LCD but all i get is kinda chinese characters or nothing instead of the key i'm pressing... i guess there's something wrong with my hserin but i can't figure what exactly. i'm new to PIC so have mercy on my soul

DEFINE HSER_RCSTA 90h
DEFINE HSER_TXSTA 20h
DEFINE HSER_BAUD 9615
DEFINE HSER_SPBRG 25
W0 var BYTE

'Set LCD Data port
DEFINE LCD_DREG PORTB
' Set starting Data bit (0 or 4) if 4-bit bus
DEFINE LCD_DBIT 4
' Set LCD Register Select port
DEFINE LCD_RSREG PORTB
' Set LCD Register Select bit
DEFINE LCD_RSBIT 2
' Set LCD Enable port
DEFINE LCD_EREG PORTB
' Set LCD Enable bit
DEFINE LCD_EBIT 3
' Set LCD bus size (4 or 8 bits)
DEFINE LCD_BITS 4
' Set number of lines on LCD
DEFINE LCD_LINES 2
' Set command delay time in us
DEFINE LCD_COMMANDUS 2000
' Set data delay time in us
DEFINE LCD_DATAUS 50
DEFINE HSER_CLROERR 1 'clear overflow error bit

pause 500
Lcdout $fe, 1
W0=0
again: HSERIN [ W0 ]
if W0 = 0 then again
Pause 500 ' Wait for LCD to startup
Lcdout $fe, 1 ' Clear LCD screen
Lcdout W0 ' Display W0
Pause 500 ' Wait .5 second
goto again