Video: Lesson 2 - Addressing modes on the 6502

6502, 65c02, and 6280 CPU programming
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akuyou
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Video: Lesson 2 - Addressing modes on the 6502

Post by akuyou » Tue Apr 23, 2019 12:58 pm

https://youtu.be/nOPI0Xbj_Yc

www.chibiakumas.com/6502/#Lesson2

The 6502 has very few registers - but it makes up for this with a mind boggling number of addressing modes!

You won't need them all at first, but you should at least understand what they all do - lets see some examples of how they work!

Lets try them all out with some simple examples!
Chibi Akuma(s) Comedy-Horror 8-bit Bullet Hell shooter! // 「チビ悪魔」可笑しいゴシックSTG ! // Work in Progress: ChibiAliens

Interested in CPU's :Z80,6502,68000,6809,ARM,8086,RISC-V
Learning: 65816,ARM,8086,6809

Super_Maryo_53
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Re: Video: Lesson 2 - Addressing modes on the 6502

Post by Super_Maryo_53 » Thu May 23, 2019 5:18 am

Hey @Akuyou, i commented on this lessons video today, about having problems running the program through the BBC emulator and i was thinking asking here would be better.
so when i try to run the lesson prog (the test data,the chunk code and example 8), it loads up correctly for a split second then goes to this: https://imgur.com/gallery/7KPvm5F
i haven't changed any of the code and i have re-downloaded the devtools; so i think it might be because i am using win 10. But i don't really know. :|
Anyway, any help would be amazing.

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akuyou
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Re: Video: Lesson 2 - Addressing modes on the 6502

Post by akuyou » Thu May 23, 2019 8:54 am

Yes, the same problem is happening my end too... it looks like a bug has crept in somewhere in the 'Monitor' code...

This should only take an hour or two to figure out... give me a moment!
Chibi Akuma(s) Comedy-Horror 8-bit Bullet Hell shooter! // 「チビ悪魔」可笑しいゴシックSTG ! // Work in Progress: ChibiAliens

Interested in CPU's :Z80,6502,68000,6809,ARM,8086,RISC-V
Learning: 65816,ARM,8086,6809

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akuyou
Posts: 315
Joined: Mon Apr 22, 2019 3:19 am

Re: Video: Lesson 2 - Addressing modes on the 6502

Post by akuyou » Thu May 23, 2019 9:46 am

Ok, I think I got it sorted... please re-download the sources file:
http://www.chibiakumas.com/6502/sources.7z

Technical bit - no need to worry about this!

I've added some more code to the common functions, and it meant the code of the example was using the areas as the 'test writes'... so the test code was corrupting the functions of the code!

I've changed the start address from $1000 to $0200, which makes enough space for the problem no longer occur
Chibi Akuma(s) Comedy-Horror 8-bit Bullet Hell shooter! // 「チビ悪魔」可笑しいゴシックSTG ! // Work in Progress: ChibiAliens

Interested in CPU's :Z80,6502,68000,6809,ARM,8086,RISC-V
Learning: 65816,ARM,8086,6809

Super_Maryo_53
Posts: 2
Joined: Thu May 23, 2019 1:59 am

Re: Video: Lesson 2 - Addressing modes on the 6502

Post by Super_Maryo_53 » Fri May 24, 2019 6:47 am

Hey Akuyou, i just got a chance to try out the new source and i'm still having the same problem :cry:
Although it's now lasting a few more seconds before going into the black screen, so now i can actually see the code in action .
I have moved on to the other lessons, since this one is more about the theory and i haven't come across any problems yet :)
Thanks again for your help and hard work! It has helped a lot.

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