> Message-ID:

David Given wrote:
> fact that the stack's limited to 256 bytes is also a bit of a problem!


Any realistic language implementation on the 6502 uses a software
stack.

> If anyone's interested, the ACK works round all of this by using an
> external stack. This is largely because of architectural restrictions


> It doesn't help that it's using this external stack *in addition to* the
> CPU stack, rather than instead of. This is the longjmp code:
> http://tack.cvs.sourceforge.net/tack...s?revision=3D2.

2&view=3Dmarkup

Eek!

> This is not how I would have done it. Needless to say, I would not
> recommend the use of this code by anyone.


A brief look through the Small-C code shows that the hardware
stack is only used for JSRing to system code. The language
implementation uses the software stack.

--
J.G.Harston - jgh@arcade.demon.co.uk - mdfs.net/User/JGH
BBC BASIC for Windows and Internationalisation
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