Syntax Error for a symbol

[rjandsam]

Hi the following code comes up with a syntax error, but when I replace sensor1 for d.6 it compiles.
Any ideas or is this an editor problem?

Thanks
Rich

#picaxe 40x2
Symbol Sensor2=d.7
Symbol Sensor1=d.6

main:
readadc10 Sensor1, b1
goto main


ERROR MESSAGE
readadc10 Sensor1, b1
^
Syntax error on line 6 at/before position 10

Error: Valid ADC channels are 0-27 only!

 

[hippy]

This is because X2 devices expect to see an ADC channel number in READADC and READADC10 commands. While the compilers can automagically determine what the ADC channel number is from a port.pin reference within the command, it cannot do that when a symbol defined as port.pin is used.

On a 40X2, pin D.6 is ADC Channel 26 and pin D.7 is ADC Channel 27, so this should work -

#picaxe 40x2
Symbol Sensor1 = 26 ; Pin D.6 / ADC 26
Symbol Sensor2 = 27 ; Pin D.7 / ADC 27

main:
readadc10 Sensor1, w1
readadc10 Sensor2, w2
goto main

You may also want to change your 'b1' variable to a word variable ( as in the above code ) when using a READADC10 which returns a 10-bit value which cannot be stored in an 8-bit byte variable.

 

[rjandsam]

Hi Hippy,

Thank you for the fast response and solution, sorry I forgot to put a word variable in it is actually in my code I just typed up a quick example of my problem.

Although your solution works fine I did notice that anything up to d.3 does compile ok.

Thanks

Rich

#picaxe 40x2
Symbol Sensor2=d.3
Symbol Sensor1=d.2

main:
readadc10 Sensor1, w1
readadc10 Sensor2, w2
goto main

 

[lbenson]

This is because d.2 has a value of 26, which is a valid ADC channel (though it's associated with pin D.6), and d.3 has a value of 27, also valid, though associated with D.7. D.7 has a value of 30, which is not a valid ADC channel number. The following code run in the simulator will show you the numeric value of D.2, D.3, and D.6:

#picaxe 40x2
sertxd(#d.2," ",#d.3," ",#d.6)