14M readtemp but not readtemp12


New Member
After much success with 08M and DS18B20 I am now trying some 14M's using version 5.1.5
readtemp 4,w1 [is working fine for me I get 19 degs etc.]

readtemp12 4,w1 [always returns 0 ]



Worth mentioning the 14M firmware version.
View/Options... Firmware?
So that other can try to replicate like for like.
(sorry, I don't have a 14M to try but it works on all other breeds).

Getting a return value of 0 will happen if the wrong pin is used, an input only pin (eg pin3) or the pull-up resistor is missing.
Double check by using an absolutely basic program that uses readtemp to w0 and readtemp12 to w1 in a loop with a debug and nothing else to remove the possibility of another part of the program from corrupting any variables.


Technical Support
Staff member
This is a known documentation/firmware issue with 14Ms, readtemp12 is not supported on these parts.


New Member
Is the situation likely to change with firmware upgrades and the like or should i just ask for my money back.



Senior Member
PICAXE's cannot have firmware upgraded, so you would have to wait and buy a 14M which has firmware support for READTEMP12 added, or switch to another PICAXE which already does.

The deciding question is, will the 14M firmware support READTEMP12 in the future ?

A stop-gap or semi-solution would be to use your 14M to control a PICAXE-08M which did the READTEMP12 and passed the data back to the 14M.


New Member
Thanks for your help guys. I'll have to wait. I have been using 08M's and could have done with an extra output. I had already decided not to go up to 18X but saw the 14M and it was too tempting (pin for pin + extra)as it was minimal redesign of my board. As luck would have it I now have a board designed to fit a 14M but is running with a 08M in it and I've got all the must have stuff running. What's the best way of finding out when/(if) an upgrade occurs.