My first Picaxe goof.

J

jscottb

Active member
So the other night I thew together an 8M2 board with a 74595 shifty and a bit of code. All was well then I unplugged the programmer and is not well then ;)

RT*M is a good thing sometimes... All better now.

 
A

AllyCat

Senior Member
Hi,

Personally, I recommend a 100k (or even higher) pulldown resistor directly from the PICaxe programming input pin to ground, (which admittedly is NOT in the Manual). That still allows the PICaxe to boot correctly, but allows a few other "tricks" such as enabling the internal Weak Pullup resistor on that pin. The problem with 10k is that you might form a potential divider with the "22k" programming resistor and get erratic (or even no) programming. Putting the 10k on the "PICaxe" side of the 22k is probably the second most common "gotcha" on the forum. ;)

Cheers, Alan.
 
J

jscottb

Active member
AllyCat said:
Hi,

Personally, I recommend a 100k (or even higher) pulldown resistor directly from the PICaxe programming input pin to ground, (which admittedly is NOT in the Manual). That still allows the PICaxe to boot correctly, but allows a few other "tricks" such as enabling the internal Weak Pullup resistor on that pin. The problem with 10k is that you might form a potential divider with the "22k" programming resistor and get erratic (or even no) programming. Putting the 10k on the "PICaxe" side of the 22k is probably the second most common "gotcha" on the forum. ;)

Cheers, Alan.
Click to expand...
Thanks. I will make my next board accordingly.

Yeah, I was using my Pic only knowledge (limited as that may be) but was like "that's not the MCLR pin, why a pulling resistor!" Did not think about the firmware looking for downloads :)

@erco I will not forget. I will have to say my kingdom has a lot of 10k resistors in it, just was not on that board. :(
 
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