1wire Dallas DS18B20 High Temperature error 127 - Raspberry Pi Forums

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hi had post in case others have same problem. searched days on net found nothing. here goes:

have 6 of these temp senders attached single 1 wire pin on pi. i'm boiling water make distilled. work ok @ temps under 50 degrees c. :d

found through trial , error whenever temp raised above 50, reading 127.937. :( when temp fell, start reading below 50. :? when reading other 127, temps right (i checked hand held ir thermometer).

problem? checked resistor, 4k7, specified, has installed separate 1k0 resistor drop voltage led. had wired wrong, , voltage across temp sensors (when worked out left check) 3.0 volts, not 3.3 being supplied pi. :oops:

shorting on 1k resistor raised voltage, , presto!, douglas adams said, add nice fresh cup of tea, , ~98c! :lol:

doubt stupid me, but, if reading this, might you. :roll:



raspberrypi



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