reifsnyderb Posted October 11, 2023 Share Posted October 11, 2023 (edited) Hello, I spent a couple hours of trying to move working DLI's. Originally, the DLI's were located well before the display list. However, I need to move the DLI's, and display list, out of the bankable code region. So, I moved the DLI's into another region and placed the Display List before the DLI's. The problems were now many and numerous. It was like a whack-a-mole game trying to get this to work. Finally, thinking about how the DLI's worked when placed before the display list, I put them before the display list. Everything now works. Did I miss some rule, somewhere, that DLI's should be before the display list? Thanks! Brian Edited October 11, 2023 by reifsnyderb Quote Link to comment Share on other sites More sharing options...
Wrathchild Posted October 11, 2023 Share Posted October 11, 2023 What are you referring to as Dlis? The interrupt code or the instructions in the display list to trigger an interrupt? The irq code location has no bearing on the location of the display list and vice-versa, you must be doing something else wrong. Can you create a cut down example? Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted October 11, 2023 Author Share Posted October 11, 2023 1 minute ago, Wrathchild said: What are you referring to as Dlis? The interrupt code or the instructions in the display list to trigger an interrupt? The irq code location has no bearing on the location of the display list and vice-versa, you must be doing something else wrong. Can you create a cut down example? Here's the code..... FIX $2A00 ; Display List Interrupt Routines ; Initial DLI -- Loads colors for graph DLI1 = * PHA LDA #low DLI2A ; Load DLI2A interrupt address STA VDSLST LDA #high DLI2A STA VDSLST+1 STA WSYNC ; Wait for horizontal sync. JSR CLRGA ; Load colors for graph PLA RTI DLI2A = * PHA LDA #low DLI2B ; Load DLI2B interrupt address STA VDSLST LDA #high DLI2B STA VDSLST+1 STA WSYNC ; Wait for horizontal sync. JSR CLRGB ; Load colors for graph PLA RTI ; Load menu colors DLI2B = * PHA LDA #low DLI3 ; Load DLI3 interrupt address STA VDSLST LDA #high DLI3 STA VDSLST+1 STA WSYNC ; Wait for horizontal sync. JSR CLRM PLA RTI ; Load textbox colors DLI3 = * PHA LDA #low DLI4 ; Load DLI4 interrupt address STA VDSLST LDA #high DLI4 STA VDSLST+1 STA WSYNC ; Wait for horizontal sync. JSR CLRTB ; Load colors text box PLA RTI ; Load copyright colors DLI4 = * PHA LDA #low DLI5 ; Load DLI4 interrupt address STA VDSLST LDA #high DLI5 STA VDSLST+1 STA WSYNC ; Wait for horizontal sync. JSR CLRC ; Load colors for copyright PLA RTI ; Load initial title colors DLI5 = * PHA LDA #low DLI1 ; Load DLI1 interrupt address STA VDSLST LDA #high DLI1 STA VDSLST+1 STA WSYNC; ; Wait for horizontal sync. JSR CLRT ; Load colors for title PLA RTI ; **************************************************************************************************************** ;FIX DSTART FIX $2B00 ;DLCODE = * ;LOC DLIMEM ;LOC $2C00 ;ORG $2B00 ;DLCS = * ; Start of display list related code ; Display List for Config Screen ;FIX $9E00 DISLST ; Display List DB $70,$70,$70 ; 24 SL DB $47 ; 16 SL DW CSTTL ; Title "MEGA 4 XL" DB $70 ; 8 SL DB $42 ; 8 SL DW STXRAM ; "0...RAM...4096" DB $CE ; 1 SL, 40 bytes for upper line on graph ; DLI1 DW SCGRLN DB $4D ; 8 SL, Gr 7 Graph, 40 byes/line - use center 32 bytes or 128 pixels DW SCGRPH DB $8D,$0D,$8D ; DLI2A, DLI2B DB $4E ; 1 SL, 40 bytes for lower line on graph DW SCGRLN DB $42 ; 8 SL DW SCGRL ; Graph Labels DB $30 ; 4 SL DB $46 ; 8 SL DW SCDRIV ; Drive Settings DB $06,$06,$06,$06,$06,$06,$06 ; 56 SL DB $06 ; 8 SL, Printer Spooler DB $46 ; 8 SL DW SCOPT ; Option Key DB $B0 ; 4 SL DLI3 DB $42 ; 8 SL DW SCMB1 ; Message Box 1 DB $10 ; 2 SL DB $42 ; 8 SL DW SCMB2 ; Message Box 2 DB $90 ; 2 SL DL14 DB $42 ; 8 SL DW SCCPR DB $80 ; 1 SL DLI5 DB $41 DB low DISLST DB high DISLST ; NOTE: 0 SL still available Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted October 11, 2023 Author Share Posted October 11, 2023 Here's the functions called from the DLI's.... FIX $2E00 ; Setup copyright colors CLRC = * LDA #$44 ; STA COLOR0 ;Large upper case characters STA COLPF0 LDA #$0C ; STA COLOR1 ;Gr.0 Text STA COLPF1 LDA #$0A ; Light grey ; STA COLOR2 ;Gr.0 Background STA COLPF2 LDA #$0A ; Light grey ; STA COLOR4 ;Background/Border color STA COLBK RTS ; Setup title colors CLRT = * ;LDA #$44 ; Red LDA #$84 ; Blue STA COLOR0 ; Large upper case characters STA COLPF0 LDA #$00 STA COLOR1 ; Gr.0 Text STA COLPF1 LDA #$0A ; Light grey STA COLOR2 ; Gr.0 Background STA COLPF2 LDA #$0A ; Light grey STA COLOR4 ; Background/Border color STA COLBK RTS ; Setup text box CLRTB = * LDA #$48 ; STA COLOR0 ;Large upper case characters STA COLPF0 ;LDA #$C9 LDA #$00 ; Black ;STA COLOR1 ;Gr.0 Text STA COLPF1 LDA #$0A ; Light grey ;LDA #$94 ; ; STA COLOR2 ;Gr.0 Background STA COLPF2 LDA #$0A ; Light grey ; STA COLOR4 ;Background/Border color STA COLBK RTS ; Setup graph colors -- upper 1/2 CLRGA LDA #$2F ; Light yellow ; STA COLOR0 ;Gr 7 graph background STA COLPF0 ; LDA #$84 ; Blue LDA #$A6 ; Torquoise ; STA COLOR1 ;Gr.7 bank color STA COLPF1 LDA #$0A ; STA COLOR2 ;Gr.0 Background STA COLPF2 LDA #$0A ; STA COLOR4 ;Background/Border color STA COLBK RTS ; Setup graph colors -- lower 1/2 CLRGB ; LDA #$2F ; Light yellow LDA GRLC1 ; STA COLOR0 ;Gr 7 graph background STA COLPF0 ; LDA #$84 ; Blue ; LDA #$A6 ; Torquoise LDA GRLC2 ; STA COLOR1 ;Gr.7 bank color STA COLPF1 LDA #$0A ; STA COLOR2 ;Gr.0 Background STA COLPF2 LDA #$0A ; STA COLOR4 ;Background/Border color STA COLBK RTS ; Setup menu colors CLRM LDA #$04 ; Dark grey ; STA COLOR0 ;Large upper case characters STA COLPF0 LDA #$00 ; STA COLOR1 ;Gr.0 Text STA COLPF1 LDA #$0A ; Light grey ; STA COLOR2 ;Gr.0 Background STA COLPF2 LDA #$0A ; Light grey ; STA COLOR4 ;Background/Border color STA COLBK RTS Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted October 11, 2023 Author Share Posted October 11, 2023 Here's a screenshot of the screen working correctly. Like I said, I've got it working. I am just wondering for future reference. Quote Link to comment Share on other sites More sharing options...
Wrathchild Posted October 11, 2023 Share Posted October 11, 2023 Some not so good practices in there: 1) DLIs trigger after the line they are on, so the last $80 followed by a $41 is not such a good idea? What is shown after this point which needs DLI to set it right? 2) What your code is depending upon is the first DLI fires the right (first) routine. Better would be to use a VBI to set the first DLI. Then the last DLI does not need to chain back to the first. 3) DLIs are quite time critical. So the chaining of the next DLI does not need to be the first thing done, it it usually the last. Also, JSR and RTS are expensive in terms of clock cycles. These routines aren't reused, so inline them. Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted October 11, 2023 Author Share Posted October 11, 2023 27 minutes ago, Wrathchild said: Some not so good practices in there: lol No surprise there. 🙂 This is the first time I've done this. 🙂 27 minutes ago, Wrathchild said: Some not so good practices in there: 1) DLIs trigger after the line they are on, so the last $80 followed by a $41 is not such a good idea? What is shown after this point which needs DLI to set it right? Are you referring to this? DB $80 ; 1 SL DLI5 DB $41 DB low DISLST DB high DISLST I did this to reset the colors for the top of the screen. Adding a VBI, like you mention in #2, would take care of this. I did find out the hard way that trying to add a DLI to the $41 results in a nasty stack overflow. lol 31 minutes ago, Wrathchild said: 2) What your code is depending upon is the first DLI fires the right (first) routine. Better would be to use a VBI to set the first DLI. Then the last DLI does not need to chain back to the first. Good idea. I have VBI enabling code already in the program but commented out. I was trying to avoid VBI's to avoid yet another complexity. (In addition to DLI's, I have PMG's so as to add more colors.) This would also save wasting that last scan line....which I suspected wasn't a good idea but didn't think of anything else. 33 minutes ago, Wrathchild said: 3) DLIs are quite time critical. So the chaining of the next DLI does not need to be the first thing done, it it usually the last. Also, JSR and RTS are expensive in terms of clock cycles. These routines aren't reused, so inline them. Good point on putting the DLI chaining last and I'll also inline the subroutines. (All they do is change the colors anyhow.) Some experimentation here makes me wonder if it's possible to reliably change colors in the middle of a scan line with some constructive delays. Thanks for the pointers! I've spent a lot of time screwing around with the Display List and the DLI's. Quote Link to comment Share on other sites More sharing options...
Wrathchild Posted October 11, 2023 Share Posted October 11, 2023 7 minutes ago, reifsnyderb said: I did this to reset the colors for the top of the screen. The OS routines are doing this for you already. Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted October 11, 2023 Author Share Posted October 11, 2023 1 hour ago, Wrathchild said: The OS routines are doing this for you already. I was pondering your statement about this and realized the trick is to set the shadow color addresses so that the OS sets the colors every VBLANK. Then, no VBI is needed. 🙂 All the DLI's then call the color changes directly to the registers. With the exception of not creating a VBI, all changes are implemented as I am letting the OS handle the first color settings via it's normal OS VBI whereby it sets the colors based on the shadow color addresses. Works great! Thanks again! Quote Link to comment Share on other sites More sharing options...
Wrathchild Posted October 11, 2023 Share Posted October 11, 2023 Just now, reifsnyderb said: Then, no VBI is needed I'd still recommend using one to set the first DLI Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted October 11, 2023 Author Share Posted October 11, 2023 Cleaned up code: ; Display List Interrupt Routines ; Initial DLI -- Loads colors for upper part of graph. DLI1 = * PHA STA WSYNC ; Wait for horizontal sync. LDA #$2F ; Light yellow background for Gr7 graph STA COLPF0 LDA #$A6 ; Torquoise color for Gr. 7 banks. STA COLPF1 LDA #low DLI2A ; Load DLI2A interrupt address STA VDSLST LDA #high DLI2A STA VDSLST+1 PLA RTI DLI2A = * PHA STA WSYNC ; Wait for horizontal sync. LDA GRLC1 ; Get first graph color color STA COLPF0 LDA GRLC2 ; Get second graph color color STA COLPF1 LDA #low DLI2B ; Load DLI2B interrupt address STA VDSLST LDA #high DLI2B STA VDSLST+1 PLA RTI ; Load menu colors DLI2B = * PHA STA WSYNC ; Wait for horizontal sync. LDA #$04 ; Dark grey STA COLPF0 ; Large upper case characters. LDA #$00 STA COLPF1 ; LDA #$0A ; Light grey LDA #low DLI3 ; Load DLI3 interrupt address STA VDSLST LDA #high DLI3 STA VDSLST+1 PLA RTI ; Load textbox colors DLI3 = * PHA STA WSYNC ; Wait for horizontal sync. LDA #$48 STA COLPF0 ; Large upper case characters. LDA #$00 ; Black STA COLPF1 LDA #low DLI4 ; Load DLI4 interrupt address STA VDSLST LDA #high DLI4 STA VDSLST+1 PLA RTI ; Load copyright colors DLI4 = * PHA STA WSYNC ; Wait for horizontal sync. LDA #$44 ; Large upper case characters STA COLPF0 LDA #$0C ; Light gray STA COLPF1 ; Gr.0 Text LDA #low DLI1 ; Load DLI1 interrupt address STA VDSLST LDA #high DLI1 STA VDSLST+1 PLA RTI Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted October 11, 2023 Author Share Posted October 11, 2023 11 minutes ago, Wrathchild said: I'd still recommend using one to set the first DLI Why use a VBI if I can just use the OS? Quote Link to comment Share on other sites More sharing options...
TGB1718 Posted October 11, 2023 Share Posted October 11, 2023 1 hour ago, reifsnyderb said: Some experimentation here makes me wonder if it's possible to reliably change colors in the middle of a scan line with some constructive delays. Like this ,not the best example as it's a graphics 0 screen, but I'm changing the colour about 1/2 way across the screen, then resetting back to the original colour until the next dli (so 8 scan lines later for GR.0) dli.asm 1 Quote Link to comment Share on other sites More sharing options...
Wrathchild Posted October 11, 2023 Share Posted October 11, 2023 (edited) 21 minutes ago, reifsnyderb said: Why use a VBI if I can just use the OS? The DLI vector at $200 is not a shadow value, it IS the indirect JMP address used by the OS to jump to when a display list interrupt occurs. Edited October 11, 2023 by Wrathchild Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted October 11, 2023 Author Share Posted October 11, 2023 (edited) 46 minutes ago, Wrathchild said: The DLI vector at $200 is not a shadow value, it IS the indirect JMP address used by the OS to jump to when a display list interrupt occurs. I didn't do anything with $200, instead, I went to $2C4 and provided the color values.... LDA #$84 ; Blue STA COLOR0 ; Large upper case characters LDA #$00 STA COLOR1 ; Gr.0 Text LDA #$0A ; Light grey STA COLOR2 ; Gr.0 Background LDA #$0A ; Light grey STA COLOR4 ; Background/Border color Then, the OS will reset them every VBLANK. Edited October 11, 2023 by reifsnyderb Quote Link to comment Share on other sites More sharing options...
Wrathchild Posted October 11, 2023 Share Posted October 11, 2023 1 hour ago, reifsnyderb said: $200 This is VDSLST, so you are using it. Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted October 11, 2023 Author Share Posted October 11, 2023 1 hour ago, Wrathchild said: This is VDSLST, so you are using it. Ok. Admittedly, I am unsure as to what the fundamental difference is, but I now have the initial colors being set by a deferred VBLANK routine. Thanks! Brian Quote Link to comment Share on other sites More sharing options...
Wrathchild Posted October 11, 2023 Share Posted October 11, 2023 3 hours ago, reifsnyderb said: LDA #low DLI1 ; Load DLI1 interrupt address STA VDSLST LDA #high DLI1 STA VDSLST+1 Hi Brian, yes you have misunderstood. You were already OK by setting the COLORx shadow registers as these are copied during the VBI. All you needed to do was to take the code above OUT of DLI4 and put this in your deferred VBI (immediate would be better but you'll be OK). 1 Quote Link to comment Share on other sites More sharing options...
phaeron Posted October 12, 2023 Share Posted October 12, 2023 The deferred VBI can be randomly skipped due to IRQ processing, so it is best to avoid it for anything that must run every frame, including resetting the DLI vector. Additionally, the deferred VBI runs after the system VBI has already copied shadow registers to hardware registers. This happens in either stage 1 or stage 2 VBI depending on the specific register, and both of these are before deferred VBI processing. If you try changing variables like COLOR4 or SDMCTL from deferred VBI, there will be a one-frame lag in the changes taking effect. For these reasons, I generally find it hard to recommend using deferred VBI for anything at all. 2 1 Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted October 12, 2023 Author Share Posted October 12, 2023 (edited) 3 hours ago, phaeron said: The deferred VBI can be randomly skipped due to IRQ processing, so it is best to avoid it for anything that must run every frame, including resetting the DLI vector. Additionally, the deferred VBI runs after the system VBI has already copied shadow registers to hardware registers. This happens in either stage 1 or stage 2 VBI depending on the specific register, and both of these are before deferred VBI processing. If you try changing variables like COLOR4 or SDMCTL from deferred VBI, there will be a one-frame lag in the changes taking effect. For these reasons, I generally find it hard to recommend using deferred VBI for anything at all. Thanks for pointing this out. I just looked at the OS source code. It appears the shadow color registers are also non-critical code and, therefore can be skipped just like a deferred VBI. I'll change it to an immediate VBI. Edited October 12, 2023 by reifsnyderb Quote Link to comment Share on other sites More sharing options...
Rybags Posted October 12, 2023 Share Posted October 12, 2023 Then you have the immediate VB problems - Too long running code can cause shadow register copies to be delayed, in extreme cases the DList pointer could be stored after the display has started which can make the screen jump. Too long running code will disrupt SIO operations. But in general for game/demo purposes immediate mode is often best. You can prevent deferred mode from being skipped but at the cost of turning off the keyboard IRQ which can be inconvenient. Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted October 12, 2023 Author Share Posted October 12, 2023 (edited) 5 minutes ago, Rybags said: Then you have the immediate VB problems - Too long running code can cause shadow register copies to be delayed, in extreme cases the DList pointer could be stored after the display has started which can make the screen jump. Too long running code will disrupt SIO operations. But in general for game/demo purposes immediate mode is often best. You can prevent deferred mode from being skipped but at the cost of turning off the keyboard IRQ which can be inconvenient. In this case, I am just setting the colors at the top of the screen. Initial testing appears fine. This is for a configuration screen for a 1090 card. 🙂 Edited October 12, 2023 by reifsnyderb Quote Link to comment Share on other sites More sharing options...
Wrathchild Posted October 12, 2023 Share Posted October 12, 2023 2 hours ago, reifsnyderb said: In this case, I am just setting the colors at the top of the screen. Initial testing appears fine. This is for a configuration screen for a 1090 card. 🙂 You can still use a VBI, as Avery pointed out "But in general for game/demo purposes immediate mode is often best." the setting of VDSLST is small and won't affect things. The danger of the deferred VBI is that the CRITIC flag will cause it to be skipped and so something important like resetting the VDSLST isn't something you can go without. With the approach of a) first setting VDSLST as part of your initialisation and then b) using DLI4 to re-point it to DLI1, you run the risk of something many of us would have seen when using DLIs and that is 'roll', which happens when say the number of DLI flags in the DLIST don't match the interrupts being used, or loop counters are used and you remove a flag but forget to adjust the counter limit. So at the end of the display the VDSLST is left pointing to the wrong routine and when the screen is next drawn and the first DLI is requested, it calls that wrong routine and things are out-of-kilt. By resetting the DLI vector to the first interrupt routine within the VBI this can help avoid that scenario and you tend to then only need to worry about under running, which generally looks like the lower area not being setup as you'd expect. 2 Quote Link to comment Share on other sites More sharing options...
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