08 pinouts

[russbow]

I want to try to modify an old 'bot' design to a picaxe. The old design uses a Pic 12c509. The picaxe toy I am looking at uses an 08. I don't like the circuit of the second, 10 FETs, but I like the prog. I don't like the prog of the first (ASM) but I like the circuit.

If I compare the pinout diagrams of the two devices, they seem to match pin for pin, even the terminology.

Can anyone see a problem with replacing a 509 directly with an 08.

Thanks, Russ

 

[Dippy]

As long as you take into consideration the programming pins for PICAXE then, on the face of it, I can't see a problem in principle. I haven't checked pins so i can't give a yes or no.

But, unless you post a schematic then we're all in Crystal Ball Mode... and mine has misted up.
Good luck.

 

[westaust55]

Pic 12c509 vs PICAXE 08M

From a quick glance at the datasheet for the Pic 12c509, yes the PICAXE 08M is pinwise compatible down to Input 3 being an input only.

PICAXE 08M has more program memory and EEPROM/RAM but as BASIC is not as efficient as assembler the extra memory will likley about balance out.

IMHO, go for it and give it a try.

 

[hippy]

The 08M appears pin compatible with a 12C509 but whether it is circuit compatible depends. If ...

* Leg 1 ever exceeds 6.5V
* Leg 2 or 3 are used for an oscillator
* Leg 2 is used as an output
* Leg 7 is used as an input
* Current into Leg 1 exceeds 95mA
* Current out of Leg 8 exceeds 95mA
* Total I/O source or sink current exceeds 90mA

Then you may not be able to simply plug an 08M in and doing so may damage the 08M; the 12C509 is electrically more robust than later PICmicros.