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#Apple Chips

#: 5027 S/General/DDJ officeForum unknown
    30-Jul-86 08:59:43
Sb: #5001-#Apple Chips
Fm: Russell McCabe 76167,1343
To: Bob Perez 70007,2336

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My apologies!!! I do recommend that (s)he get K&R. Also a few of Jack Purdum's books on C. I have yet to see ANYTHING for the 8086/88 in the way of assembly language tutorials that'd be worth buying, period. The nearest to even partially acceptable I've seen is Structured Assembly Language for the IBM PC. I don't remember the author's name, just that you can get it at a Waldenbooks store in the Computer Books section. I'd also recommend getting Peter Norton's books for the IBM PC-both of them-and use all three of them as the tutorial needed. Total cost? About $60.00, but that includes 6% sales tax. The reason I included the obscure stunts was that their equivalents are almost mandatory for the 6502 microprocessor. A decent case construct on the 6502 uses either the X register or the stack and the same is true for a jump table. The use of the 16 bit shifts and the byte swapping example aren't exactly obscure, since they're things that you'd run into in everyday programming. The use of the XCHG opcode for sorting is obvious, especially since you would be using an index register to point to one of the operands. Bit flipping is something that goes with the territory. I'll admit that the sneaky write to the stack segment could have been done more simple by pushing the address onto the stack. Perhaps a better example would have been mov bx, sp push word ptr ss:[bx] for a fast way to duplicate what's on top of the stack without risk of knu'd have to do something like la pha pha and enable and disable interrupts, taking 5 instructions to do what it takes an 8088 3 instructions to do. Remember that a segment override IS an instruction. It also helps(sometimes) for a beginner to see examples that correspond to familiar things. I'm assuming that he is pretty up on the tricks a 6502 can do and play on you and making use of that assumption. Regards, Russ