[Energia Library] OneWire DS18B20 (430 & Stellaris)

[Rickta59 589]

For what it's worth, I was able to use this successfully with P2_0.

 

Thanks!

-rick

[arvo 0]

Thanks for all, i just switch to hardware UART, and this work's fine, but can't find DS18B20... :-(

[pivden 6]

check the hardware:

Vcc to Vcc

GND to GND

DQ (DATA) to P2.1

resistor (4.7K or 2-6K) from Vcc to P2.1

 

P2.1 defined in code:

#define OWPIN  9

https://github.com/energia/Energia/wiki/Hardware#wiki-LaunchPad_MSP430G2553

 

pinouts:

http://datasheets.maximintegrated.com/en/ds/DS18B20.pdf

 

Figure 5. Powering the DS18B20 with an External Suppl

[arvo 0]

pivden, big thanks! The problem was in my resistor!

To Mr. OzGrant: Your library working good, thanks!

[moderboy 1]

Is there any solution to use this code with DS18S20 sensors?

[OzGrant 22]

Moderboy,

Sorry taken so long to get back. Have got  DS18 code on my other old PC. Will dig it up and put in ASAP..

Grant

[maksms 0]

del

[mahmutbeg 0]

Hi,

 

I'm trying to get this code(sample code from archive) running on my launchpad, but all I'm getting is 

OW1=85C (when I use parasite wiring),

and not recognizing device when I use external supply wiring ..

[Register 3]

Hi,

 

The result is an int but the 18b20 has more resolution than 1 degree, no?

 

Regards.

[jxlbbb 2]

Hi, 

 

Here is a small change to StellarisOW.ino that will provide full resolution without adding floats.

the binary size remains very small :

Binary sketch size: 4,771 bytes (of a 131,072 byte maximum) (MSP430F5529)

 

:

 

change 

 

byte result[MAXOW+5];

to 

int32_t  result[MAXOW+5];

 

change the saveTemperature(uint8_t ROMno) routine to 

 

void saveTemperature(uint8_t ROMno){

  result[ROMno] = (int32_t)((data[1] << 8) | data[0]);

}

 

change 

         Serial.print(result); 

to 

 

         prt2((result*625)/100);

 

add the prt2 routine 

 

 

void prt2(int x){

    Serial.print(x/100);

    Serial.print(".");

    Serial.print(x%100);

}

 

 

output is now

 

OW1=20.56C OW2=20.62C 

 

Hope this will help some !

 

jxlbbb

 

[OzGrant 22]

jxlbbb,

Yup that works great

Grant

[Marco 0]

Hi, I work with texas launchpad MSP430G2553 and DS18B20. I download GFDS18B20V2.zip and I follow the instructions. I use a 4.7k resistor pull-up. My problem is that I can't find the device. Anuone help me? Thanks.

[pane 0]

 

G'day,

I now have a working Dallas Library that works on both 430 and Stellaris using Energia IDE.

Have fun.

Grant

 

Hi OzGrant!

 

Thank you for the usefull OW library (I use it to read  DS18B20). It works great for me on MSP430G2553.

 

The same code with new Energia 0012 and TM4C129 LaunchPad gives me the following error msg

 

 

C:\DOCUME~1\Mama\LOCALS~1\Temp\build596613283320066190.tmp\core.a, -LC:\DOCUME~1\Mama\LOCALS~1\Temp\build596613283320066190.tmp, -lm, -lc, -lgcc, -LC:\DOCUME~1\Mama\LOCALS~1\Temp\build596613283320066190.tmp, -lm]

 

GFDS18B20V2\GFDS18B20.cpp.o: In function `DS18B20::DS18B20(unsigned char)':

C:\Documents and Settings\Mama\Dokumenty\Energia\libraries\GFDS18B20V2/GFDS18B20.cpp:46: undefined reference to `port_to_dir'

C:\Documents and Settings\Mama\Dokumenty\Energia\libraries\GFDS18B20V2/GFDS18B20.cpp:46: undefined reference to `port_to_ren'

C:\Documents and Settings\Mama\Dokumenty\Energia\libraries\GFDS18B20V2/GFDS18B20.cpp:46: undefined reference to `port_to_input'

C:\Documents and Settings\Mama\Dokumenty\Energia\libraries\GFDS18B20V2/GFDS18B20.cpp:46: undefined reference to `port_to_output'

collect2.exe: error: ld returned 1 exit status

 

Thanks for help or hint,

Pavel

[OzGrant 22]

Pavel,

Will have a TM4C129 in a couple of days and check it out.

Grant

[jeffman54 0]

This problem seems to be caused because the defined macros portDirRegister, portRenRegister, portInputRegister, and portOutputRegister in GFDS18B20.cpp refer to arrays port_to_dir[],  port_to_ren[], port_to_input[] and port_to_output[] which are normally externally defined in the msp430 pins_energia.h file.

 

The current TM4C129 pins_energia.h file found under the lm4f/variants/launchpad_129 directory doesn't define these arrays and appears to use a totally different base referencing scheme for the pin ports.

 

I think it will take a bit more work to get the port register mechanism used for the MSP430 to operate for the TM4C.

 

Jeff