R: Re: CSG 4510 and 4567 and Dmagic reverse engineering

Many many thanks for explanation :)

Best, Carlo

>----Messaggio originale----
>Da: msmcdoug@iinet.net.au
>Data: 26/07/2010 19.12
>A: <cbm-hackers@musoftware.de>
>Ogg: Re: CSG 4510 and 4567 and Dmagic reverse engineering
>
>Hi,
>
>Nate is quite correct, for the most part, but let me add my $0.02 worth...
>
>Old chips were designed by engineers laying out "micro-circuits" much as 
>you'd lay out a full printed-circuit board. Hardware-description langauges 
>(HDLs) like Verilog weren't used for that back then (despite being invented 
>in the 80's).
>
>Newer programmable devices, such as CPLDs, FPGAs and ASICs can be programmed 
>using HDLs like Verilog or VHDL. However, just like you can't rip the C 
>source from an executable, you can't rip the Verilog source from even these 
>programmable devices.
>
>A reasonable number of older devices have been *emulated* in HDLs in recent 
>years, mainly by studying the datasheets - often there is enough information 
>in the chip data to allow a full emulation without any reverse-engineering 
>required. Such devices include 8- and 16-bit CPUs, support chips such as 
>sound, PIAs, video etc. Even whole computers - including the C64 & Amiga 500 
>- have been emulated in HDLs on a single programmable chip.
>
>For chips that don't have any data, or insufficient data, "decapping" is 
>what Nate is describing, and the techniques are only now being refined. 
>Usually decapping is required for protected CPUs with hidden ROMs, for 
>example, as you'd find in certain arcade games. But it requires expensive 
>equipment and a lot of knowledge about how chips are put together - not for 
>the home hobbyist.
>
>Regards,
>
>-- 
>|              Mark McDougall                | "Electrical Engineers do it
>|  <http://members.iinet.net.au/~msmcdoug>   |   with less resistance!"
>
>       Message was sent through the cbm-hackers mailing list
>



       Message was sent through the cbm-hackers mailing list