Changes

Programming:Unlocking ASIC

373 bytes added, 9 April
/* Patent */
Once the ASIC is unlocked, we get access to a new [[Gate Array]] register called RMR2. It is accessible in the same way as other Gate Array registers.
 
Locking the ASIC again doesn't disable any of its functionality, it just prevents you changing it. [https://www.cpcwiki.eu/forum/programming/asm-source-code/msg249856/#msg249856 Source]
<br>
<pre>
di ; v3.0 1 -> 30 bytes!
ld bc,#BCFF
out (c),c
add hl,hl ; h = 5432 10**
xor h:and #F7:xor h ; a = 7765 1321
add hl,hl ; h = 4321 0***
ld l,a ; l = 7765 1321
ld a,h ; a = 5432 10**rla ; a = 4321 0***
and #88:xor l ; a = (7 xor 4)765 (1 xor 0)321
cp c
= Patent =
For one reason or another, Amstrad has patented the verification mechanism ([[Media:Patent GB2243701A.pdf|GB2243701A]]). The patent seems to focus on ''verifying'' (rather than on ''sending'') the sequence, so its legal use is a bit unclear.
On the [[Original Arnold V Specs]] - Issue 1.5 - 10th April 1990, it is precised at §2.11 "Locking of enhanced features":
</code>
According to [https://patents.google.com/patent/GB2243701A/en Google patents for GB2243701A] the patent was withdrawn on 1994-12-21. This means that this particular patent cannot be enforced.
<br>
[[Category:Programming]]
[[Category:CPC Plus]]
13,056
edits