MIKE ROSS wrote in a message to Greg Mayman:

 MR> "Greg Mayman" wrote to "Roy J. Tellason" (04
Jan 03  08:49:00)  ---
 MR> on the topic of "THOSE OLD EXPENSIVE [1/2]"

 -=> Roy J. Tellason said to Greg Mayman
 -=> about "THOSE OLD EXPENSIVE [1/2]" on 01-02-03  04:06.....

 RJT> Yes indeed,  though I still want to make an EPROM emulator...

 GM> CMOS RAM chip plus a backup battery, sitting in a wirewrap
 GM> socket. It usually needs a couple of extra components, such as
 GM> isolation diodes on the Vpp, and a write enable switch.

 MR> I could never understand the point of an Eprom emulator. I mean if
 MR> the program works why not simply burn the eprom and be done with
 MR> it. If it has a bug then simply erase the eprom and start again.
 MR> Why the need for an emulator that may cost hundreds of dollars?

Because of two things:  First,  such an emulator likely won't cost hundreds
of dollars,  not any more at least,  unless you're buying something of the
sort as a "professional product" in the embedded systems market, 
where I think that a lot of stuff is seriously overpriced.  And secondly, 
there's the time factor -- it takes *time* to pull an eprom,  erase it, 
and burn a new copy with a bugfix.  With an emulator you avoid those
hassles,  especially for minor program bugs that can be patched "on
the fly" by maybe only changing a small number of bytes.  It makes the
process of doing such work a whole lot more interactive...

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