Search found 25 matches

by larsbrinkhoff
Thu Jun 09, 2016 11:06 am
Forum: Coding
Topic: Obtaining m68k-atari-mint-gdb
Replies: 10
Views: 6547

Re: Obtaining m68k-atari-mint-gdb

I cloned https://github.com/vinriviere/m68k-atar ... nutils-gdb, and checked out the binutils-2_26-mint branch.

Then I ran

Code: Select all

./configure --target=m68k-atari-mint --disable-gdb
make
by larsbrinkhoff
Fri Apr 15, 2016 5:08 am
Forum: Coding
Topic: ST Chipset decap
Replies: 128
Views: 36249

Re: ST Chipset decap

I have implemented the reload logic in software. It's a bit of a mess, but it seems to work.
by larsbrinkhoff
Tue Apr 12, 2016 1:04 pm
Forum: Coding
Topic: Best emulator for debugging
Replies: 20
Views: 7836

Re: Best emulator for debugging

The oSTis debugger is virtually identical to MonST. If that's your thing.

Image
by larsbrinkhoff
Tue Apr 12, 2016 12:33 pm
Forum: Coding
Topic: Variable LOAD-pixel delay (shifter wakestates)?
Replies: 10
Views: 5022

Re: Variable LOAD-pixel delay (shifter wakestates)?

troed wrote:1) "Spectrum 512 black pixels" - one shift (cycle) happens before xxxxx-palette-lookup-available-something


Is there a (stable) test case for this?
by larsbrinkhoff
Tue Apr 12, 2016 8:43 am
Forum: Coding
Topic: Sync-tricks/fullscreen discussion
Replies: 90
Views: 27677

Re: Sync-tricks/fullscreen discussion

troed wrote:I've spent some time with the GLUE statemachine for ST/STE not only in 50Hz but also 60Hz (and 71Hz, but I still need to wrap my head around a few things there).


Thanks, I think that's a good improvement.

Regarding 71... is there a LINE = 224 too?
by larsbrinkhoff
Fri Apr 08, 2016 11:22 am
Forum: Coding
Topic: ST Chipset decap
Replies: 128
Views: 36249

Re: ST Chipset decap

ijor wrote:Here you go ...

LOAD pulse is one cycle, and they look to me one cycle wide on Dio's traces.


Thank you, kind sir!

You're right about LOAD, I'll have to adjust my eyeballs.
by larsbrinkhoff
Thu Apr 07, 2016 6:52 pm
Forum: Coding
Topic: ST Chipset decap
Replies: 128
Views: 36249

Re: ST Chipset decap

EDIT: goofed.
by larsbrinkhoff
Thu Apr 07, 2016 6:52 pm
Forum: Coding
Topic: ST Chipset decap
Replies: 128
Views: 36249

Re: ST Chipset decap

The logic outputs one clockpixel cycle pulse after four LOAD pulses since the previous Reload, at the next 16 pixels boundary. Thank you. I'm a bit outside my domain with this hardware stuff, but it's becoming more clear. It might be helpful to look at the waveforms I posted previously. Yes, those ...
by larsbrinkhoff
Thu Apr 07, 2016 11:51 am
Forum: Coding
Topic: ST Chipset decap
Replies: 128
Views: 36249

Re: ST Chipset decap

Basically the logic outputs a one cycle (at the pixel clock) pulse, every 16 pixels, but only if four LOADs have been performed since the last reload. In theory this should be one pulse every 16 CPU cycles. How does this work in medium and high resolutions? Is this pixel clock always 8 MHz, regardl...
by larsbrinkhoff
Thu Apr 07, 2016 10:18 am
Forum: Coding
Topic: ST Chipset decap
Replies: 128
Views: 36249

Re: ST Chipset decap

stefanberndtsson wrote:what's the role of the pxCtrLoad signal?


I'm guessing that's the signal to copy the contents of the IR registers to RR.

EDIT: Nope, guess not.
by larsbrinkhoff
Wed Apr 06, 2016 6:57 am
Forum: Coding
Topic: ST Chipset decap
Replies: 128
Views: 36249

Re: ST Chipset decap

SHIFTER shift registers reload control logic schematics (now complete ): Thank you! This is so yummy! Only, I'm a hardware illiterate, so I can't read this. It's clear to me that the bottom part outputs a reload signal every four LOADs. But I guess this reload must somehow be synchronised with the ...
by larsbrinkhoff
Wed Apr 06, 2016 6:30 am
Forum: Coding
Topic: Variable LOAD-pixel delay (shifter wakestates)?
Replies: 10
Views: 5022

Re: Variable LOAD-pixel delay (shifter wakestates)?

I'm not a hardware person. This is my mental model, and how I percieve the terminology. When two clocks (or more generally, signals) are synchronised , there is some fixed constant number c such that if the amplitudes of the signals are described by functions f and g , f(x) = g(x+c) If c=0 , then th...
by larsbrinkhoff
Wed Apr 06, 2016 5:54 am
Forum: Coding
Topic: ST Chipset decap
Replies: 128
Views: 36249

Re: ST Chipset decap

Now I dream about a new emulator, working at low level (same level as you describe). Could be a bit slow but will emulate perfectly all ATARI video tricks (even "closure" demo by Sync) without any high level emulation hack. Your dreams are coming true. We're working on making "oSTis&...
by larsbrinkhoff
Thu Mar 31, 2016 11:59 am
Forum: 680x0
Topic: Wakeup modes
Replies: 73
Views: 31209

You get instability when you have a different number of internal registers filled in the Shifter when it starts to draw a frame than you have when it has ended drawing it. If you have 0 registers filled, the screen will start at the normal PAL start. If you have 1 register filled or use the NTSC fo...
by larsbrinkhoff
Thu Mar 31, 2016 5:12 am
Forum: 680x0
Topic: Rasters
Replies: 40
Views: 14784

Re: Rasters

npomarede wrote:if you do a "STOP #2100" while an HBL int is already pending, you will see that the total time for stop + interrupt + E clock jitter will never go below 8+56+0


Do those 8 cycles include reading two words for the STOP instruction? (Or prefetching the next...)
by larsbrinkhoff
Wed Mar 30, 2016 9:19 am
Forum: Coding
Topic: Is it possible to de-ice/jam/etc on a PC?
Replies: 24
Views: 10718

Re:

leonard wrote:Anyone have a C code to ICE pack something?


aktiv8 wrote:This is in C Leonard, hopefully will be what you require
http://www.nocrew.org/software-pack-ice.html


It's at GitHub now:

https://github.com/larsbrinkhoff/pack-ice
by larsbrinkhoff
Wed Mar 30, 2016 9:17 am
Forum: Coding
Topic: horizontal scrolling on ST
Replies: 569
Views: 118554

Re: horizontal scrolling on ST

troed wrote:Thanks to NoCrew's 4 pixels raster-trick (ADD/MOVE*) it's indeed possible in special cases to switch back'n'forth in four cycles.


I must put an end to this rumour that NoCrew ever did something useful. The technique was discovered by TOS-Crew.
by larsbrinkhoff
Wed Mar 30, 2016 9:12 am
Forum: 680x0
Topic: 68000 clock cycles table
Replies: 160
Views: 65509

Re:

alien wrote:Of course another avenue of research, which may/may not be fruitful, is trying NoCrew's 4 cycle enable/disable technique.

ljbk wrote:Yes, i remember now about this 4 pixels wide "rasters" demo.


Credit where credit is due! It was TOS-Crew, not NoCrew.
by larsbrinkhoff
Tue Mar 29, 2016 7:26 pm
Forum: Coding
Topic: Sync-tricks/fullscreen discussion
Replies: 90
Views: 27677

Re: Sync-tricks/fullscreen discussion

ijor wrote:The IR => RR transfer logic seems to synchronize pixel shifting with four LOADs, and also uses DE as part of the synchronization.


How is DE involved in in the synchronization?
by larsbrinkhoff
Tue Mar 29, 2016 10:56 am
Forum: 680x0
Topic: Rasters
Replies: 40
Views: 14784

Re: Rasters

ijor wrote:It is possible to use STOP and keep synced, we (Paulo and me) did it some time ago. Check the "long" 68000 thread for more info.


Sorry, I'm late to the party. Which thread is that?
by larsbrinkhoff
Wed Mar 23, 2016 6:51 am
Forum: Coding
Topic: Variable LOAD-pixel delay (shifter wakestates)?
Replies: 10
Views: 5022

Variable LOAD-pixel delay (shifter wakestates)?

The textbook answer is that there is an 18-cycle delay from the assertion of LOAD, until the first pixel is displayed. Of course, if some shifter IR registers are loaded before the start of the line, the delay would be lower: one of 6, 10, or 14. I'm curious about the 2-cycle delay that is added on ...
by larsbrinkhoff
Tue Mar 22, 2016 11:11 am
Forum: Coding
Topic: Sync-tricks/fullscreen discussion
Replies: 90
Views: 27677

Re: Sync-tricks/fullscreen discussion

ijor wrote:If say, you are running code from Rom, you could access GLUE with a different shift.


I envison a future where all the hottest cutting-edge demos are running out of cartridges. Gotta get that two-cycle precision!
by larsbrinkhoff
Mon Mar 21, 2016 11:25 am
Forum: Development
Topic: Source code moved to Github
Replies: 4
Views: 7593

Re: Source code moved to Github

The GitHub repository seems rather domant. Does active development happen somewhere else?
by larsbrinkhoff
Sun Mar 20, 2016 11:08 am
Forum: Coding
Topic: Sync-tricks/fullscreen discussion
Replies: 90
Views: 27677

Re: Sync-tricks/fullscreen discussion

Steven Seagal wrote:Hmm, new competitor in emulation soon?


Not really. It's more of a fun toy. We're not focused on emulation performance, but simple code and working towards cycle-accurate simulation of most components.

https://github.com/nocrew/ostis
by larsbrinkhoff
Sat Mar 19, 2016 7:13 am
Forum: Coding
Topic: Sync-tricks/fullscreen discussion
Replies: 90
Views: 27677

Re: Sync-tricks/fullscreen discussion

Hello,

I'm writing a detailed software simulator of the GLUE-MMU-Shifter, so I'm watching this thread and the corresponding wiki page with great interest.

Thanks for all the great information so far!

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