Re: Transwarp IIe revisited

[Roger Johnstone <roger@roger.geek.nz.removethisbit>]

In <4759caf7$0$16653$9b4e6d93@newsspool3.arcor-online.net> Linards 
Ticmanis  wrote:

> I received a 1.4 ROM file from David and put it to use, now "0" and 
> "1" both work. (Though I ask myself why in the world did AE use 
> windowless EPROMs that can't be erased?)

Purely for the cost. The window requires a ceramic IC package, while OTP 
EPROMs (one-time programmable erasable programmable read-only memories) 
can be housed in a cheap plastic package. Even if the ROM needs upgraded 
at some point the vast majority of owners or even service agents 
wouldn't have an EPROM eraser and programmer to do it, so would have to 
ship the EPROM back to a service centre. The shipping and handling would 
probably cost more than the price difference between a OTP and erasable 
EPROM, so it's cheaper to use the OTP part and throw it away when 
upgrading.

-- 
* Roger Johnstone, Invercargill, New Zealand -> http://roger.geek.nz
* PS/2 Mouse Adapter for vintage Apple II or Mac
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