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journal:spring2019:bmeehan1:week6

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journal:spring2019:bmeehan1:week6 [2019/02/28 09:05]
bmeehan1 [MONTH Day, YEAR]
journal:spring2019:bmeehan1:week6 [2019/02/28 09:17] (current)
bmeehan1 [Feb 28, 2019]
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 The assembly language for 6502 starts with a 3 character code for the instruction "​opcode"​. There are 56 instructions,​ 10 of which you will use frequently. Many instructions will have a value after the opcode, which you can write in decimal or hex. If that value starts with a # then it means use the actual number. If the value doesn'​t have then # then it means use the value at that address. So LDA #$05 means load the value 5, LDA $0005 means load the value that is stored at address $0005. The assembly language for 6502 starts with a 3 character code for the instruction "​opcode"​. There are 56 instructions,​ 10 of which you will use frequently. Many instructions will have a value after the opcode, which you can write in decimal or hex. If that value starts with a # then it means use the actual number. If the value doesn'​t have then # then it means use the value at that address. So LDA #$05 means load the value 5, LDA $0005 means load the value that is stored at address $0005.
  
-dw = data word= 2 bytes+.dw directive is a Data Word (1 word = 2 bytes)
 =====sysprog week6===== =====sysprog week6=====
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journal/spring2019/bmeehan1/week6.txt · Last modified: 2019/02/28 09:17 by bmeehan1