HP-IB disc drive emulation program available

[Tony Duell]

> 
> On Thursday 17 December 2009, Tony Duell wrote:
> > The thing is that I suspoect (without reading the data sheets) that
> >  most microcontrollers can't meet the HPIB spec on their port pins,
> >  you need to put something between the port and the 24 pin
> >  microribbon connector. Might as well be one of the chips designed
> >  for the purpose.
> > 
> > In any case I have an objection to linking an expensive (probably)
> > custom-programmed (certianly) part to an external connector that's
> >  going to be linked to $deity-knows-what. Much easier to replace a
> >  buffer chip if somethign goes wrong than replace the
> >  microocontroller and have to program it again.
> 
> I see "meeting specs" as a potential problem (though if it's the only 
> device on the bus besides the controller, , you can probably "get away" 

'Getting away with it' is something I will do for quick hacks on my own 
bench, but not for stuff likely to be used by others, or stuff I depend 
on. 

> with it).  However, the microcontroller may easily be less expensive to 
> replace than the HPIB buffer (especially if you compare the price for 
> each new/NOS).

Possibly. I said 'easier', not 'cheaper' though. The point being that the 
buffer chip doesn't have to be programemd, so it can be replaced by 
somebody who doesn't have a programmer for whatever microcontroller is 
used. Most modern microcotnrollers (at least ones with enough I/O for 
this) come in a surface-mount package, the buffers certainly were 
available in DIPs (and could be socketed).

Repair cost != component cost...

-tony