Subject: Re: [stella] Collaboration From: Thomas Jentzsch <tjentzsch@xxxxxx> Date: Mon, 20 Jan 2003 19:13:32 +0100 |
I wrote: > There are 6 free cycles in the playfield code, but we would need 8 for > doing this: > lda RAM1,x > and #%01010101 > sta PF1 > lda RAM2,x > and #%01010101 > sta PF2 > lda RAM1,x > and #%10101010 > sta PF1 > lda RAM2,x > and #%10101010 > sta PF2 After a little bit more thinking about it, I came up with this solution: lda RAM1,x and #%10101010 sta PF1 eor RAM1,x sta PF2 lda RAM2,x and #%10101010 sta PF1 eor RAM2,x sta PF2 This saves 4 cycles. Currently this still doesn't fit well into the existing kernel, but I already know how to save 11 bytes and with some compromises we might even get the whole 22 bytes. Have fun! Thomas _______________________________________________________ Thomas Jentzsch | *** Every bit is sacred ! *** tjentzsch at web dot de | ---------------------------------------------------------------------------------------------- Archives (includes files) at http://www.biglist.com/lists/stella/archives/ Unsub & more at http://www.biglist.com/lists/stella/
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