6502.org Forum  Projects  Code  Documents  Tools  Forum
It is currently Fri Nov 22, 2024 1:00 am

All times are UTC




Post new topic Reply to topic  [ 82 posts ]  Go to page Previous  1, 2, 3, 4, 5, 6
Author Message
PostPosted: Wed Feb 03, 2021 6:31 pm 
Offline

Joined: Wed Nov 11, 2020 10:42 pm
Posts: 104
Location: Kelowna Canada
Hi Daryl
Glad to see work progressing, looking forward to further updates especially for PI 3 as I have a few of them (not all in use).
Larry


Top
 Profile  
Reply with quote  
PostPosted: Tue Feb 16, 2021 4:05 pm 
Offline
User avatar

Joined: Tue Aug 11, 2020 3:45 am
Posts: 311
Location: A magnetic field
Firstly, I quite like the allocation of seperate cores to multi-media. This provides the most immediate performance boost.

Secondly, I am curious to know how much of this work can be deployed on MCL65+.

Thirdly, I strongly recommend augmenting the six bit RRGGBB palette with two least significant intensity bits shared across all channels. (See 16*16 Pixel Tile Video Display And Video Codec for subjective test results across four 8 bit palettes.) At the very least, common intensity bits provide 16 shades of gray rather than four.

_________________
Modules | Processors | Boards | Boxes | Beep, Beep! I'm a sheep!


Top
 Profile  
Reply with quote  
PostPosted: Tue Feb 16, 2021 10:36 pm 
Offline
User avatar

Joined: Fri Aug 30, 2002 9:02 pm
Posts: 1748
Location: Sacramento, CA
Sheep64 wrote:
Firstly, I quite like the allocation of seperate cores to multi-media. This provides the most immediate performance boost.

Yes it does, and with 4 cores, there's room for more.

Quote:
Secondly, I am curious to know how much of this work can be deployed on MCL65+.

I am not familiar with the Teensy4.1 and do not use Arduino, so I cannot really answer this.

Quote:
Thirdly, I strongly recommend augmenting the six bit RRGGBB palette with two least significant intensity bits shared across all channels. (See 16*16 Pixel Tile Video Display And Video Codec for subjective test results across four 8 bit palettes.) At the very least, common intensity bits provide 16 shades of gray rather than four.

This could be done, but I found the 64 color choices seemed ample. I will try some experiments with this suggestion when I get time.

Thanks for your input!

Daryl

_________________
Please visit my website -> https://sbc.rictor.org/


Top
 Profile  
Reply with quote  
PostPosted: Mon Feb 22, 2021 5:50 am 
Offline
User avatar

Joined: Fri Aug 30, 2002 9:02 pm
Posts: 1748
Location: Sacramento, CA
okwatts wrote:
Hi Daryl
Glad to see work progressing, looking forward to further updates especially for PI 3 as I have a few of them (not all in use).
Larry

I have the Pi3 SD versions loaded on my website. Feel free to give them a try and let me know if you have any problems. The "manual" says Pi2 but its the same for either version.

https://sbc.rictor.org/pisim.html

Daryl

_________________
Please visit my website -> https://sbc.rictor.org/


Top
 Profile  
Reply with quote  
PostPosted: Mon Jun 26, 2023 8:31 am 
Offline
User avatar

Joined: Sat Dec 01, 2018 1:53 pm
Posts: 730
Location: Tokyo, Japan
8BIT wrote:
In core 2, I have a 320x200 display set up with 63 colors ( 2 bits for each Red, Green, & Blue). I have it set up as 4 addresses in the simulator IO space
$8040 = pixel color - 0x00RRGGBB
$8041 = Y coordinate 0 - 199, above that and the pixel will not get plotted
$8042 = X coordinate low byte
$8043 = X coordinate high byte 0-319, above that and the pixel will not get plotted

A write to $8044 will tell core2 to plot the point.

I like that interface.

Just one comment: you might be able to get a fair efficiency boost, especially for doing things like clearing the screen, by changing it so that a write to $8042, the X coordinate low byte, triggers a plot. Then a lot of the plotting time for some common operations would simply be incrementing and writing the X co-ordinate.

_________________
Curt J. Sampson - github.com/0cjs


Top
 Profile  
Reply with quote  
PostPosted: Mon Jun 26, 2023 4:08 pm 
Offline
User avatar

Joined: Fri Aug 30, 2002 9:02 pm
Posts: 1748
Location: Sacramento, CA
I'd have to check to see if the plot engine could keep up, or if you might miss a point. I have a poll for engine ready status to prevent missing plots. Unfortunately, I dont have spare time to test right now. I'll keep this on my to-do list.

Thanks for the suggestion!

Daryl

_________________
Please visit my website -> https://sbc.rictor.org/


Top
 Profile  
Reply with quote  
PostPosted: Mon Jun 26, 2023 7:31 pm 
Offline
User avatar

Joined: Sat Dec 01, 2018 1:53 pm
Posts: 730
Location: Tokyo, Japan
8BIT wrote:
I'd have to check to see if the plot engine could keep up, or if you might miss a point.

Yeah, that occured to me, but I couldn't think of a good solution for it so I thought that maybe ignoring the problem would work. :-)

Perhaps generate wait states on write when not ready? Though that of course just slows the CPU.

MSX machines have this issue with their VDPs (TMS9118 and friends). There might be something in all the work that's been done on that that could help, but it probably is a bit of a rabbit hole.

_________________
Curt J. Sampson - github.com/0cjs


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 82 posts ]  Go to page Previous  1, 2, 3, 4, 5, 6

All times are UTC


Who is online

Users browsing this forum: No registered users and 8 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to: