kamath@reed.UUCP (03/16/87)
hello networld. . . There have been a lot of questions about the 65C02 vs. the 6502, and replacing the C02 with an 802. So, I thought it might be better to clear the air a little. Replacing any chip in you //e or ][+ will not change the speed, except for the PAL/HAL divider and the JK flipflops which devide and clean up the crystal. Therefor, putting in a new microprocessor will NOT speed up your computer. So why bother? Well, power consumption and heat dissapitation are two pretty good reasons. The 'C' in the processor name means CMOS, and they run cooler and with less power then their non-c counterparts. When they introduced the 65C02 they increased the instuctions set and addressing modes. However, you can buy both c and non-c 65802's and 816's. Another reason is, as mentioned above, the 65C02 has more features. There is no difference between a 65802 and 65816. They are the same silicon chip. The 802 is pin for pin compatable with the 6502 and also powers up in 6502 emulation mode. The only advantage to having a 65802 instead of a 6502 or 65C02 in a //e is that IF THE PROGRAMMER WHO WROTE THE SOFTWARE USES IT! it will not speed up applesoft, the monitor, anything, except that which takes advantage of it. It is NOT like putting a 450 horsepower engine into an MG midget. At all. It is more like buying a very expensive linear track turntable for your old 1950's beat up chubby checkers records. They wont really sound any better, but if you buy NEW chubby checkers records, they will sound better than if you played them on your old beater turntable. As for speed up boards, as far as I know, the fastest a 6502 can go is 3MHz (6502B). 65C02 - 4MHz. I don't know how fast the 802 and 816 go, but I am sure that in a little while (if not already) they'll have 8 MHz versions out. So if you have a speedup board that runs at 2 MHz, you might as well have a 6502 in it as a 802! Unless the SOFTWARE takes advantage of it. The only real advantage or a 802 over a 65C02 is 16 bit registers. Sean Kamath kamath@reed.edu.UUCP tektronix!reed!kamath P.S. Sorry about typos and such, I just woke up. And I was up all night arbitrating between my three cats and the one that's visiting for a week. At least I didn't go into RISC, pipelining and orthogonality. I didn't want to get technical :-) sean
daveh@cbmvax.cbm.UUCP (Dave Haynie) (03/17/87)
in article <5705@reed.UUCP>, kamath@reed.UUCP (Sean Kamath) says: > As for speed up boards, as far as I know, the fastest a 6502 can go is > 3MHz (6502B). 65C02 - 4MHz. I don't know how fast the 802 and 816 go, > but I am sure that in a little while (if not already) they'll have 8 MHz > versions out. So if you have a speedup board that runs at 2 MHz, you > might as well have a 6502 in it as a 802! Unless the SOFTWARE takes > advantage of it. > > Sean Kamath > kamath@reed.edu.UUCP > tektronix!reed!kamath As of last fall, GTE, who's the only vendor of 65C802s and 65C816s, had 2MHz versions of both in quantity, 4MHz versions of the 65802s to whomever wanted them, and enough 65C816s to sell to Apple for around $8 a piece. They hadn't produced anything in the 65C02 line at 4MHz yet in production quantities, though they were in the process of redesigning the 65C02 to run at 4MHz. Rockwell MAY have had 4MHz 65C02s longer, I'm not sure about them. MOS, who invented the 6502, only makes NMOS versions, and their fastest 6502 family chip is the the C128, running at 2.04MHz. Most of the data sheets supplied on 65C02s list 4MHz parts, and the 65C802/65C816 data sheets list 8MHz parts. The reason for this is, in very small quantites, you can probably get these parts, or some close to them. I know GTE can deliver a 6MHz 65C802, but these are basically just 4MHz parts that pass the 6MHz test. They're hand picked; OK for hobbiests or small companies that make accelerator cards, but useless for big companies that Apple that sometimes make 20,000 computers a month or more. -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Dave Haynie Commodore Technology // /| ___ __ __ __ {ihnp4|caip|rutgers}!cbmvax!daveh |\ // /_| | / \ / \ / \ Commodore rarely admits to knowing me, \\// / | +--+ | | | | | | much less sharing my personal opinions. \/ / | |___ \__/ \__/ \__/ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~