larryw@pro-dchamber.UUCP (Larry Walewski) (02/01/90)
In-Reply-To: message from yu-r@ketch.cis.ohio-state.edu I own a Laser 128, and was wondering if changing to a 65c802 would speed this computer up? Surely a $16 chip cannot do the same as a $100 Zip Chip? Will changing to the 65c802 increase my 1Mhz speed?
greyelf@wpi.wpi.edu (Michael J Pender) (02/02/90)
In article <202.apple.net@pro-dchamber> larryw@pro-dchamber.UUCP (Larry Walewski) writes: >In-Reply-To: message from yu-r@ketch.cis.ohio-state.edu > >I own a Laser 128, and was wondering if changing to a 65c802 would speed >this computer up? Surely a $16 chip cannot do the same as a $100 Zip Chip? >Will changing to the 65c802 increase my 1Mhz speed? In a nutshell, not really. The real advantage lies in the ability to port sections of 65816 code, and to use the new instructions in programs you write yourself if you're a programmer. However if you're a programmer you can make MUCH faster code by making use of these new instructions. For example, the following routine does a copy of a page of memory: First store the source and destination addresses in the zero page locations correspoding to source and dest, then... ldy #$00 2 cycles loop lda (source),y 5 cycles sta (dest),y 6 cycles iny 1 cycle bne loop 3/2 cycles This will take roughly 16 + 255 * 15 = 3841 clock cycles. On the 65c802, first set up the x and y registers to the LSB within each page, then: mvp #>source,#>dest 7 clock cycles Proper use of the features of this chip should provide a drastic speed increase. But it should not noticably affect the execution speed of porgrams written for the IIc/e. Having a 65c802 does not allow one to run all IIgs software, we don't have the GS toolbox nor sound, nor graphics. In fact it doesn't really make the 65c02 capable of anything it wasn't before. But if used properly, it does it much more elegantly (and damn quick...) --- Michael J Pender Jr Box 1942 c/o W.P.I. ... (Mankind) has already greyelf@wpi.bitnet 100 Institute Rd. used its last chance. greyelf@wpi.wpi.edu Worcester, Ma 01609 - Gen. MacArthur
greyelf@wpi.wpi.edu (Michael J Pender) (02/02/90)
In article <7537@wpi.wpi.edu> greyelf@wpi.wpi.edu (Michael J Pender) writes: ...apple 6502 routine deleted... > >This will take roughly 16 + 255 * 15 = 3841 clock cycles. >On the 65c802, first set up the x and y registers to the >LSB within each page, then: > > mvp #>source,#>dest 7 clock cycles > I've been informed by Dave Seah that its more like 7 cycles/byte moved, which in this case is 1792 cycles. I'm sorry if I mislead anyone, but as I don't have my chip yet, I can't test it out myself yet. Even so, use of this chip's new functions make the block move over twice as fast: 3841/1792 = 2.14...
brianw@microsoft.UUCP (Brian WILLOUGHBY) (02/13/90)
In an article rafael t yu <yu-r@cis.ohio-state.edu> writes: > >. with the 65c802 you won't >be able to run any true 16-bit software, but you computer will work a little >faster than using the 4Mhz 65c02. Clarification: Your computer will only run faster if you rewrite the software - sometimes twice as fast. If you execute 65C02 code, then the 65C802 executes it at the same speed (or actually slower if the 65C802 is set to 6502 Emulation mode - the 65C802 is actually MORE compatible with the 6502 than the 65C02 is in the area of clock cycles per instruction). You can run "true" 16-bit software, the only hitch is that you cannot run 16-bit software that was written for GS/OS or that uses other GS-specific resources (i.e. 16 Meg addresses). There is nothing preventing an older Apple ][ from running 16-bit software, but you can't turn a ][ Plus into a GS only by changing the processor. > Also, if you are going to order the chip from Jameco make sure to specify for >the 4Mhz version. They have several versions and I'm pretty sure you don't >want to end up with a 1Mhz. I wouldn't recommend ordering the 'C802 from JameCo, although I do recommend JameCo highly for other products. An engineer at WDC warned me that JameCo had old stock (although that could be different now), and he attributed some of my 'C802 problems to the fact that I had a very early version of the 'C802. Western Design Center is a much better source of NEW 65C802 parts. Call them at 602/962-4545. Their minimum order is $50, which is higher than JameCo, but it is worth the extra trouble to purchase the latest revision of the 65C802. Perhaps someone could organize and Net purchase (sorry, I already have too many 4, 8 and 10MHz 65C802s!). BTW, I also do not recommend JameCo's own brand of Apple expansion products - they usually have cheaper parts that aren't to spec. As a specific example, their 16K RAM card came with 200ns DRAMs and did not work on my friend's Apple ][ Plus until he replaced the DRAMs with 150ns parts (the same speed as came with my Language Card form another vendor). In article <76435@tut.cis.ohio-state.edu> rafael t yu <yu-r@cis.ohio-state.edu> writes: > > I believe that the 10Mhz 65C816 are at about $100 if you buy it individually >and lower prices for bigger orders. The address I believe is: Where did you get that price? About a year ago, they were from $17.80 for 4 MHz to $24.84 for 10 MHz. IF THEY HAVE THEM IN INVENTORY. WDC sells out of every batch that they get. And don't forget to ask them for data sheets. They were more than happy to supply me with data sheets on about three or four of their 6502 superset chips, some with RAM, ROM, timers and serial and parallel ports built in! P.S. If anyone has any particular problems getting a 65C802 working in their Apple ][ Plus, feel free to send me some email. I've had to do a lot of debugging of various alternate processors for the Apple, so I might be able to help. Brian Willoughby UUCP: ...!{tikal, sun, uunet, elwood}!microsoft!brianw InterNet: microsoft!brianw@uunet.UU.NET or: microsoft!brianw@Sun.COM Bitnet brianw@microsoft.UUCP
yu-r@carp.cis.ohio-state.edu (rafael t yu) (02/13/90)
To Brian willoughby >> >> I believe that the 10Mhz 65C816 are at about $100 if you buy it individually >> and lower prices for bigger orders. The address I believe is: > >Where did you get that price? About a year ago, they were from $17.80 >for 4 MHz to $24.84 for 10 MHz. IF THEY HAVE THEM IN INVENTORY. WDC >sells out of every batch that they get. Well I calL WDC by the end of December last years and the price they give me was $95 each 65C816 plus S&H. for the 10MHz chip. Maybe your prices are a little bit old, try calling WDC for prices. A year ago, high speed 65C816 were not in demand as they are now. More people are asking for them, they have fewer every time, solution increase price and get a big profit (Isn't this the way market is suppose to work?). Now if you think the price I got of $95 was to much, I believe I read somewhere in the net that the 10MHz 65C816 are now at $104.