Video: Lesson P33 - Bitmap Graphics on the Camputers Lynx

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akuyou
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Video: Lesson P33 - Bitmap Graphics on the Camputers Lynx

Post by akuyou » Wed Apr 24, 2019 12:44 pm



www.chibiakumas.com/z80/platform4.php#LessonP33

The Camputers Lynx has a very unusual screen layout, it's screen memory conflicts with the normal memory, the effect of this is we cannot use the stack during the writing procedure when we have the video ram paged in.

Lets take a look at how to get graphics onscreen on the Lynx!
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

g0blinish
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Re: Video: Lesson P33 - Bitmap Graphics on the Camputers Lynx

Post by g0blinish » Fri Sep 25, 2020 4:42 am

Thank you for the great tutorial!

How do you think- which way is better for draw 8color pixels? use macros ScreenDrawRedBlue and ScreenDrawGreen ?

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akuyou
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Re: Video: Lesson P33 - Bitmap Graphics on the Camputers Lynx

Post by akuyou » Sat Sep 26, 2020 11:50 pm

Unfortunately, I've been told my Grime Z80 doesn't actually work on the real 'Camputers lynx' - it exhibits graphical glitches that do not occur on the emulator.

I don't have real hardware so I don't know how to fix the issue - I think it may be because I'm writing out of Vblank, but not doing so would be horrifyingly slow - so please bear that in mind when using my tutorials, and considering my reply below.

Re Macros - I think for the camputers lynx you really need to optimize the code for the situation you're looking at, the 'best' code for drawing 8x8 tiles won't be the best for, say a solid fill of a line - use the macros as a starting point, but try to optimize the code to use the regular and shadow registers to transfer the data as quickly as possible with as few 'paging operations' as you can.... I managed to make quite a few improvements to the tile code in this way for Grime Z80.
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

g0blinish
Posts: 4
Joined: Thu Sep 24, 2020 12:27 pm

Re: Video: Lesson P33 - Bitmap Graphics on the Camputers Lynx

Post by g0blinish » Mon Sep 28, 2020 3:03 pm

I do not quite understand how bank switches works.

crashes on ;RED

of course simple way is to call PLOT routine from ROM, but I'm interested in VRam write
clynx.zip
(2.31 KiB) Downloaded 8 times

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