Problems about pic thermometer

N

Novel

Guest
Now I am doing a pic thermometer which use the LM19 temperature sensor
to measure the temperature and display on the 2*16 LCD without
backlight.
And I have a pic18f45k20 microcontroller chip and 4504N adc converter.
I have connect the temp sensor to pin 9 of the pic18f45k20.
Now I just want to ask who can give me help with the codes to let this
system works.
Thanks.
 
In article <b58c264e-e04d-4844-bb3e-
fcccc141600f@s19g2000vbp.googlegroups.com>,
ntacao998@gmail.com says...
Now I am doing a pic thermometer which use the LM19 temperature sensor
to measure the temperature and display on the 2*16 LCD without
backlight.
And I have a pic18f45k20 microcontroller chip and 4504N adc converter.
I have connect the temp sensor to pin 9 of the pic18f45k20.
Now I just want to ask who can give me help with the codes to let this
system works.
Thanks.
Click to expand...
When it comes to micros, we're happy to
help people who can show they've tried
coding it on their own first.

If you have code that you've written,
post some, and we'll be glad to help
debug it. For free.

If you want us to write it for you, we
charge by the hour...

===
First off, Google doesn't show much data
on a 4504N ADC. Can you provide a link
to a datasheet?

Secondly, we'd need to know a bit about
the LCD. Different brands use different
input signals and command sets.

Thirdly, do you need the 4504N? The
'45K20 has an internal 10-bit ADC on
board. If you don't need more than
10-bit accuracy, the code would probably
be simpler if you used the internal ADC.

Fourthly, what do you mean you 'connect
the temp sensor to pin 9'? Depending on
the package (pdip, qfn, tqfp), that
could be any of three different analog
inputs.
 
On Mar 4, 4:36 am, Novel <ntacao...@gmail.com> wrote:
Now I am doing a pic thermometer which use the LM19 temperature sensor
to measure the temperature and display on the 2*16 LCD without
backlight.
And I have a pic18f45k20 microcontroller chip and 4504N adc converter.
I have connect the temp sensor to pin 9 of the pic18f45k20.
Now I just want to ask who can give me help with the codes to let this
system works.
Thanks.
Click to expand...
You have to use the CVI software
 
On 4 Mar, 01:54, Randy Day <randy....@shaw.cax> wrote:
In article <b58c264e-e04d-4844-bb3e-
fcccc1416...@s19g2000vbp.googlegroups.com>,
ntacao...@gmail.com says...

Now I am doing apicthermometerwhich use the LM19 temperature sensor
to measure the temperature and display on the 2*16 LCD without
backlight.
And I have a pic18f45k20 microcontroller chip and 4504N adc converter.
I have connect the temp sensor to pin 9 of the pic18f45k20.
Now I just want to ask who can give me help with the codes to let this
system works.
Thanks.

When it comes to micros, we're happy to
help people who can show they've tried
coding it on their own first.

If you have code that you've written,
post some, and we'll be glad to help
debug it. For free.

If you want us to write it for you, we
charge by the hour...

===
First off, Google doesn't show much data
on a 4504N ADC. Can you provide a link
to a datasheet?

Secondly, we'd need to know a bit about
the LCD. Different brands use different
input signals and command sets.

Thirdly, do you need the 4504N? The
'45K20 has an internal 10-bit ADC on
board. If you don't need more than
10-bit accuracy, the code would probably
be simpler if you used the internal ADC.

Fourthly, what do you mean you 'connect
the temp sensor to pin 9'? Depending on
the package (pdip, qfn, tqfp), that
could be any of three different analog
inputs.
Click to expand...
Thank you for answering me.
Firstly, the address of datasheet of ADC converter is
http://www.datasheetcatalog.com/datasheets_pdf/M/C/1/4/MC14504BCP.shtml.
Secondly, the part number of LCD is PMC1602C-SYR.
Thirdly, I really need ADC converter. What I need to do is to test the
connection on the board and finally to finish on the PCB.
Fourthly, I connect the Vout of the temp sesor to the AN6/WR#/RE1 pin
9 of the microchip_18F4XK20.

I never learned c language before, I feel difcult to work it out. What
I want to know now is how to display the voltage value of the temp
sensor on the LCD. After that, I know how to use the eqn. for
temperature and voltage to show the temperature on the LCD.

The following was the code I have figure out. I could not going on and
do not know whether they are right or wrong.

[Main.c]

#include "p18f45k20.h"
#include "delays.h"
#include "lcd.h"

#pragma udata // declare statically allocated uinitialized variables


#pragma code // declare executable instructions


void main (void)
{
// set internal oscillator to 4MHz
OSCCON = 0x50; // IRCFx = 101
OSCTUNEbits.PLLEN = 0; // x4 PLL disabled


lcd_init(); // initialise display
// write first screen
lcd_goto(0x00); // goto 1st line position 3


lcd_puts ("PIC Thermometer"); // write string to display
lcd_goto(0x44); // second line position 4
lcd_puts ("Runnin..."); // write second line

Delay10KTCYx(255); // delay approx 2.5 Seconds

lcd_clear(); // clear lcd
lcd_goto(0); // 1st line position 1
lcd_puts("Temperature is:");
lcd_goto(0x40);
lcd_puts
("lalalala.."); //
I just use lalalala to inst. temperature what I want.


Delay10KTCYx(255); // delay approx 2.5 Seconds
while(1);
}

void Timer0_Init(void)
{
INTCONbits.TMR0IF = 0; // clear roll-over interrupt flag
T0CON = 0b00000001; // prescale 1:4 - about 1 second
maximum delay.
TMR0H = 0; // clear timer - always write
upper byte first
TMR0L = 0;
T0CONbits.TMR0ON = 1; // start timer
}

void ADC_Init(void)
{
ANSEL = 0; //turn off all other analog inputs
ANSELH = 0;
ANSELbits.ANS6 = 1; // turn on RE1 analog
ADCON0 = 0b00011001;
}

unsigned char ADC_Convert(void)
{ // start an ADC conversion and return the 8 most-significant bits of
the result
ADCON0bits.GO_DONE = 1; // start conversion
while (ADCON0bits.GO_DONE == 1); // wait for it to complete
return ADRESH; // return high byte of result
}
 
Thank you for answering me.
Firstly, the address of datasheet of ADC converter is
http://www.datasheetcatalog.com/datasheets_pdf/M/C/1/4/MC14504BCP.shtml.
Click to expand...
That's not an ADC, that's a TTL/CMOS level
shifter. Why do you need one of those?

Secondly, the part number of LCD is PMC1602C-SYR.
Click to expand...
Does your LCD already display 'PIC
Thermometer'? Then you're 75% of the way
there.

Thirdly, I really need ADC converter. What I need to do is to test the
connection on the board and finally to finish on the PCB.
Fourthly, I connect the Vout of the temp sesor to the AN6/WR#/RE1 pin
9 of the microchip_18F4XK20.
Click to expand...
Are the +V and Gnd pins of the LM19
connected to the +V and ground of the
'45K20? You'll get screwy results if
they're not...

I never learned c language before, I feel difcult to work it out. What
I want to know now is how to display the voltage value of the temp
sensor on the LCD. After that, I know how to use the eqn. for
temperature and voltage to show the temperature on the LCD.

The following was the code I have figure out. I could not going on and
do not know whether they are right or wrong.
Click to expand...
Three points:
You have ADC_Init and ADC_Convert, but
you do not call them in your main()
routine.

Your ADC_Init should set the TRIS bit
for RE1; that will make it an input
pin rather than a TTL output.
You need to ensure that the ADFM bit
is set to your preference. You also
must clear some bits in the ADCON1
register.

Your ADC_Convert returns the ADRESH
value, but ignores the ADRESL value.
You'll need both to get a meaningful
reading.
===
Once you have the 10-bit value for
your reading (ADRESH:ADRESL), you'll
have to convert it to an ASCII string
for display on the LCD.

> [Main.c]
 
On Tue, 3 Mar 2009 15:36:47 -0800 (PST), Novel <ntacao998@gmail.com>
wrote:

Now I am doing a pic thermometer which use the LM19 temperature sensor
to measure the temperature and display on the 2*16 LCD without
backlight.
And I have a pic18f45k20 microcontroller chip and 4504N adc converter.
I have connect the temp sensor to pin 9 of the pic18f45k20.
Now I just want to ask who can give me help with the codes to let this
system works.
Thanks.
Click to expand...
Sounds like someonei n need of a simpler solution.

The PICAXE microcontrollers (PIC with a BASIC interpreter) can read
the DS18B20 temperature chip and report directly in degrees C.

Home Page: http://www.rev-ed.co.uk/picaxe/

Support Forum: http://www.picaxeforum.co.uk/
Go there and search for DS18B20

The PICAXE chips start at $3US, the DS18B20 is priced similarly.

The compiler for the PICAXE is a free download.

John
 
On 4 Mar, 23:19, Randy Day <randy....@shaw.cax> wrote:
Thank you for answering me.
Firstly, the address of datasheet of ADC converter is
http://www.datasheetcatalog.com/datasheets_pdf/M/C/1/4/MC14504BCP.shtml.

That's not an ADC, that's a TTL/CMOS level
shifter. Why do you need one of those?

Secondly, the part number of LCD is PMC1602C-SYR.

Does your LCD already display 'PICThermometer'? Then you're 75% of the way
there.

Thirdly, I really need ADC converter. What I need to do is to test the
connection on the board and finally to finish on the PCB.
Fourthly, I connect the Vout of the temp sesor to the AN6/WR#/RE1 pin
9 of the microchip_18F4XK20.

Are the +V and Gnd pins of the LM19
connected to the +V and ground of the
'45K20? You'll get screwy results if
they're not...



I never learned c language before, I feel difcult to work it out. What
I want to know now is how to display the voltage value of the temp
sensor on the LCD. After that, I know how to use the eqn. for
temperature and voltage to show the temperature on the LCD.

The following was the code I have figure out. I could not going on and
do not know whether they are  right or wrong.

Three points:
You have ADC_Init and ADC_Convert, but
you do not call them in your main()
routine.

Your ADC_Init should set the TRIS bit
for RE1; that will make it an input
pin rather than a TTL output.
You need to ensure that the ADFM bit
is set to your preference. You also
must clear some bits in the ADCON1
register.

Your ADC_Convert returns the ADRESH
value, but ignores the ADRESL value.
You'll need both to get a meaningful
reading.
==> Once you have the 10-bit value for
your reading (ADRESH:ADRESL), you'll
have to convert it to an ASCII string
for display on the LCD.



[Main.c]- Hide quoted text -

- Show quoted text -
Click to expand...
Thank you very much.
 
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