$CSB211@LSUVM.BITNET (mark orr) (05/05/90)
< caution flames ahead >
i've owned an apple ii since 1977 and they have given me years
of reliable (more or less) service. unfortunately, i cannot
say the same for the apple computer inc. I have watched, along
with you, as apple has gone from a company that ardently supported
the ii to a megacorporation on the verge of telling 5,000,000
installed and loyal users that they can just jack off.
we arent asking for crays (or even vaxes). if apple had made
credible upgrades we would not be having this discussion.
simply put "sorry, we blew it" is not going to do. a faster
CLOCK SPEED IS A START. BUT I'D LIKE TO MAKE A CASE FOR THE
68000. I HAVE BEEN USING ONE IN MY APPLE II FOR YEARS AND FIND
IT MUCH EASIER TO CODE THAN THE 6502 (I DONT HAVE A GS).
TO ILLUSTRATE WHAT EVEN A FEEBLE 68000 CAN DO I'D LIKE TO CALL
YOUR ATTENTION TO AN ARTICLE THAT APPEARED IN DECEMBER 1982
----
THAT COMPARED SIX APPLE COPROCESSORS (THE NUMBER NINE BOOSTER 6502C, 6502C,
the computer station ffp 9511, alf ad8088, stellation two mill (6809),
coprocessors 88card (8088), and the dtack grounded 68000)
the results of their benchmark:
interpreted | compiled
|
primes FPlot roots | primes fplot roots
|
6502 53 34 51 | 43 26 49
(1.0 MHz) |
|
9511 29 15 5 | 24 n/a 9
|
8088 23 15 10 | 15 7 8
|
6502c 15 10 15 | 12 8 14
(3.6 MHZ) |
|
68000 20 13 5 | 12 5 3
(6 MHz) |
|
Combo 8 6 2.8 | 6 4 2.1
(68000+
6502c)
THE PRIMES PROGRAM IS SIMILAR TO THE SIEVE BENCHMARK, THE FPLOT
USES GRAPHICS TO PLOT MANY SINES AND COSINES AND THE ROOTS BENCHMARK
COMPUTES 1000 SQUARE ROOTS. PRIMITVE BENCHMARKS - BUT THIS WAS '82
I BOUGHT MY APPLE IN '77, GOT A MOUNTAIN MUSIC BOARD (16 VOICES)
IN '81, A NUMBER NINE GRAPHICS BOARD (NEC 7220 - 512X512 RES.) IN
'83, AND TWO SAYBROOK 68000'S (EACH 12.5 MHZ) AND A TITAN ACCELERATOR
II IN '84, REPLACING IT WITH A ROCKET CHIP THIS YEAR. MY SYSTEM
HAS BETTER GRAPHICS, SOUND, AND IS MUCH FASTER THAN THE IIGS.
SO DON'T SAY THE TECHNOLOGY IS TOO HARD TO APPLY TO THE APPLE
BECAUSE IT WAS AVAILABLE (MOST OF IT WAS) BEFORE '84 (AND MORE
IMPORTANTLY IT WAS CHEAP - THE 68K'S COST ME LESS THAN $1200)
SOMEONE ASKED IF WE HAVE SEEN THE PRICE OF HIGH SPEED PROCESSORS
LATELY. I HAVE - JAMECO LISTS 12 MHZ 68000 CHIPS AT ABOUT $13
A PIECE, LESS THAN $10 IN BULK. APPLE COULD EASILY PUT A HALF
DOZEN IN AN APPLE II WITHOUT RUNNING UP A BIG BILL. APPLE COULD
HAVE PUT 68K'S IN APPLE IIE'S WHEN THEY FIRST CAME OUT.
FOR A NEW APPLE II - THINK ABOUT A THREE PROCESSOR SYSTEM:
ONE 68K FOR A CPU - EMULATING 65816 INSTRUCTIONS AND
RUNNING ITS OWN RICH INSTRUCTION SET
A 68K HANDLING GRAPHICS - RUNNING VGA-TYPE GRAPHICS
AND A 68K HANDLING I/O AND SOUND. AMIGA'S USE A SIMILAR CONCEPT
EXCEPT THEY USE SIMPLE 8 BIT PROCESSORS TO DO THE GRAPHICS
AND I/O DIRTY WORK. JUST KEEP TELLING YOURSELF 68K'S ARE CHEAP.
(BECAUSE THEY ARE) MY SAYBROOK BOARDS CONTAIN LESS THAN $80
WORTH OF PARTS (TODAYS PRICE FOR THE SUPPORT CHIPS). IF YOU
WANTED TO TAKE THE EMULATOR BURDEN OFF THE MAIN 68K, A MIXED
65816/68000 SYSTEM COULD BE DEVELOPED. A HIGH PERFORMANCE SYSTEM
NEED NOT HAVE EXPENSIVE PARTS - JUST A CLEVER DESIGN.
MY APPLE II RUNS A LIGHTNING FAST ACCELERATED APPLESOFT ON THE
68K AND I CAN CONTROL BOTH 68K'S THROUGH MACHINE LANGUAGE.
I GENERALLY USE ONE 68K TO HANDLE GRAPHICS (SENDING COMMANDS TO
THE NUMBER NINE GRAPHICS BOARD) AND ONE TO CRUNCH NUMBERS. ON THE
ABOVE TABLE MY SYSTEM EASILY OUTPERFORMS THE COMBO 6502C+SLOW 68K
and can smoke any '386.
AND I CAN RUN UNIX SYSTEM V TOO!
JUST A SUGGESTION
MARK ORR | "YOU'RE NOT GOING TO BE HAPPY
$CSB211@LSUVM.SNCC.LSU.EDU | UNTIL YOU CUT YOURSELF WITH IT!!"
@LSUVM (BITNET) |toddpw@tybalt.caltech.edu (Todd P. Whitesel) (05/05/90)
[ these are intended as friendly comments, it's late so please don't take any offense if I sound like I am flaming ] It's a lot harder to turn your mega-add-on system into a single computer than you think. One thing that startled me about board design is that unless you use really rare or expensive parts, motherboard costs are dominated by board size and through-holes, and not by parts cost. Your proposed system would not be very cost-effective compared to a 65816-based system with coprocessors custom designed by Apple. (By the way, the Amiga's coprocessors are all 16 bit -- they have to be because they all fight for the the same block of RAM.) Your add-ons probably total up to the cost of a Mac II, so I would compare their combined resolution/speed/etc to a Mac II and not the IIGS. Don't knock the 65816 until you've tried it. It doesn't make programming trivial but is efficient enough to work well once you understand it. I have written a bresenham's line drawer for the GS (optimized for 320 mode) that is entirely software and whose critical loop takes 70 clock cycles to execute. I am about to build a frame grabber board that uses a 65xxx to control VRAMs by using NMI's on horizontal blanking. The 65816 is deceptively simple. Many high-level operations on the 68000 and 8086 require short instruction sequences on the 65816, but often execute in about the same number of clocks. The frequency of appearance of these operations is such that the 65816's one byte opcodes make for a nice tradeoff. The 65816 has a lot of stack primitives which make compiled languages easier. Zero Page has been turned into Direct Page, and like the Stack may by ANYWHERE in the lowest 64K of memory. The address space has been bumped up to 16 Mb and there are enough addressing modes to adequately support it. There are a couple things missing but since the opcode space is full (with two 'escapes' for 32 bit and math coprocessing) I finally had to admit that Mensch did a good job of extending the 6502. (But he can't make faster chips to save his life. Thank God for ASIC! 20 mhz to the people!! AE get your grubby paws off!) The basic point is, to build a better Apple //, you don't need a 68000 and in many ways it is actually a detriment because by the time you have supported it properly -- You've got a Mac! The GS's 2.5 Mhz clock is the real problem -- GS/OS and a Transwarp (7 mhz) are proof that you don't need a 68000 to have a responsive desktop machine. Todd Whitesel toddpw @ tybalt.caltech.edu