16F877A and Sensirion SHT21

[ctravel]

Hi,

does anyone here have a picbasic code for reading the SHT21 using 16F877A.

i tried I2CREAD and I2CWRITE commands and it does not work.

[katelara]

The first issue, obviously, is memory. There's no 16F or 18F PIC available with >256kB memory, I think the most memory you can get in the 8bit ones is 128kB - so you're going to need an external memory of some sort.

[CuriousOne]

I also want to use this sensor, but how it is related to available memory?

[ctravel]

it worked fine now. My mistake was to use SHT21 in hold master mode.

the built in I2CREAD and I2CWRITE on Picbasic works perfectly on SHT21 but in No-Hold Master Master mode only . It took me several days to make it work.

[CuriousOne]

Can you please share the code how to work with SHT21 ?

[revelator]

Maybe if we ask nicely? Please ....or at least point us in the right direction....

Hold Master mode or No Hold Master
mode. In the first case the SCL line is blocked (controlled
by sensor) during measurement process while in the latter
case the SCL line remains open for other communication
while the sensor is processing the measurement.

Can you please share the code how to work with SHT21 ?

[iw2fvo]

Could anyone share the code for reading the sht21 or the si7021 please ?
Thanks
Ambro

[Scampy]

If you don't need the precision of the SHT21, then use any of the DHT11, DHT21, DHT22, AM2302 sensors and the library file here http://www.picbasic.co.uk/forum/showthread.php?t=19975

[iw2fvo]

thanks ,
I do really need the si7021 .
Ambro