masks: and, or, set clear & xor, Architecture
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. logical ops
and or not xor gates truth tables

. masks
bit pattern set: mask plus or al = 1101 0001 set bit 3 leave others as were or al, 0000_1000b clear: mask plus and al = 1101 0001 clear bit 3 leave others as were and al, 1111_0111b

. xor as encryption and clear
xor al, mask ; encrypt xor al, mask ; decrypt clear - fast xor al,al

. 16 bits = 1 mb of addresses??
16 bit address = 65536 addresses (2^16) 16 bit 8086 architecure supported 1 MB of memory how?: IP is 16 bits such as 0100h CS is 16 bits such as 0700h code segment memory was segmented 0700 0100 ----- 07100 or IP + (CS * 16) So we could have 16 segments of 64k = 1 megabyte 2^4 2^16 = 2^20

. architecture
view from assembly language programmer amd and intel are different implementations of same (8086) architecture apple (motorola) is a different architecture mips is different architecture risc ( vs cisc intel) fetch fast ip advance is fast lots of simple, fast instructions

. cards
1 statement per card compile and punch object deck turn-around time "desk check"