Coolcrab Posted October 1, 2017 Share Posted October 1, 2017 Hey all, I came across this book on amazon. Is it any good? I couldn't find a topic on it on the forum (But the title is very generic, so maybe I missed it.) https://www.amazon.co.uk/Making-Games-Atari-2600-Steven/dp/1541021304/ref=sr_1_4?s=books&ie=UTF8&qid=1506863939&sr=1-4&keywords=atari+2600 1 Quote Link to comment Share on other sites More sharing options...
+Random Terrain Posted October 1, 2017 Share Posted October 1, 2017 There are a few posts about it, but no one seems to say much about it. Here's the best post that pops up if you search for Steven Hugg: atariage.com/forums/topic/267271-new-to-programming/?p=3824228 Quote Link to comment Share on other sites More sharing options...
popmilo Posted October 1, 2017 Share Posted October 1, 2017 Hey all, I came across this book on amazon. Is it any good? I couldn't find a topic on it on the forum (But the title is very generic, so maybe I missed it.) https://www.amazon.co.uk/Making-Games-Atari-2600-Steven/dp/1541021304/ref=sr_1_4?s=books&ie=UTF8&qid=1506863939&sr=1-4&keywords=atari+2600 Yes it is ! Lot's of info about 2600 in one place explained in clear way. Nothing out of ordinary or that you can't find somewhere else. Price point is not on the low side, but if you like to read and you're serious about making (and finishing) a game for a2600, go for it Quote Link to comment Share on other sites More sharing options...
Jinroh Posted October 5, 2017 Share Posted October 5, 2017 I bought it, really nice book. It's a handy reference when I don't feel like pulling up the web, or just wanna read about some Atari code. Quote Link to comment Share on other sites More sharing options...
EvoMikeUK Posted October 12, 2017 Share Posted October 12, 2017 I recommend getting the book for the sake of it..... however just get Batari Basic and read the Random Terrain guides. That would be more fruitful. Quote Link to comment Share on other sites More sharing options...
G-type Posted October 16, 2017 Share Posted October 16, 2017 I like the book a lot. Quote Link to comment Share on other sites More sharing options...
SavedByZero Posted July 11, 2019 Share Posted July 11, 2019 (edited) Hey all, newbie here. I need some help with this book for chapter 8, in particular the part beginning with "YPos .byte" and ending where I'm supposed to set the address bus to #5 and then sta YPos. Mainly, this doesn't work. Nothing ever gets passed to the variable YPos unless I initialize it. If I don't leave the initialization value blank, as that part of the book seems to imply, then the Y position will be whatever I initialize the variable to. Otherwise, it's 0, and there's a big old blue line beneath the cat head sprite I'm putting on the screen. (speaking of that, where is the cowboy sprite written out in this chapter? I'm a little frustrated with the way this book is organized since the example snippets don't seem to match up to any actual code samples I can find if I really need to reference them). I started out in Basic when I was a kid, programmed a game in GRASP when I was 15-16, did a smattering of Assembly in college, then mentally became lazy and out of shape as I became dependent on ECMAScript style languages, so I'm a bit out of it. Also note: if I hard code the Y position, it also works and the blue line vanishes. But I want to do this the right way. Edited July 11, 2019 by SavedByZero Quote Link to comment Share on other sites More sharing options...
easmith Posted July 14, 2019 Share Posted July 14, 2019 On 7/11/2019 at 5:09 PM, SavedByZero said: Hey all, newbie here. I need some help with this book for chapter 8, in particular the part beginning with "YPos .byte" and ending where I'm supposed to set the address bus to #5 and then sta YPos. Mainly, this doesn't work. Nothing ever gets passed to the variable YPos unless I initialize it. If I don't leave the initialization value blank, as that part of the book seems to imply, then the Y position will be whatever I initialize the variable to. Otherwise, it's 0, and there's a big old blue line beneath the cat head sprite I'm putting on the screen. (speaking of that, where is the cowboy sprite written out in this chapter? I'm a little frustrated with the way this book is organized since the example snippets don't seem to match up to any actual code samples I can find if I really need to reference them). I started out in Basic when I was a kid, programmed a game in GRASP when I was 15-16, did a smattering of Assembly in college, then mentally became lazy and out of shape as I became dependent on ECMAScript style languages, so I'm a bit out of it. Also note: if I hard code the Y position, it also works and the blue line vanishes. But I want to do this the right way. I have this book and it has been quite helpful . Can you post your code ? I can send you some code snippets that use this routine . I have the cat head program somewhere Quote Link to comment Share on other sites More sharing options...
Dionoid Posted July 15, 2019 Share Posted July 15, 2019 Yes, it's a solid book on Atari 2600 assembly programming. I also recommend Andrew Davies book "Atari 2600 Programming for Newbies": http://www.lulu.com/shop/andrew-davie/atari-2600-programming-for-newbies-revised-edition/paperback/product-23644281.html Quote Link to comment Share on other sites More sharing options...
SavedByZero Posted July 18, 2019 Share Posted July 18, 2019 On 7/13/2019 at 10:32 PM, easmith said: I have this book and it has been quite helpful . Can you post your code ? I can send you some code snippets that use this routine . I have the cat head program somewhere Yup. The relevant code is simply: YPos .byte LDA #5 Sta YPos Simply put, the address bus value isn’t being stored in YPos. YPos stays to whatever I initialize it to. This is early chapter 8 code, which has no accompanying source on the website. thanks! Quote Link to comment Share on other sites More sharing options...
easmith Posted July 21, 2019 Share Posted July 21, 2019 On 7/17/2019 at 10:22 PM, SavedByZero said: Yup. The relevant code is simply: YPos .byte LDA #5 Sta YPos Simply put, the address bus value isn’t being stored in YPos. YPos stays to whatever I initialize it to. This is early chapter 8 code, which has no accompanying source on the website. thanks! posy the entire program please. Or send it to me through messenger if you do not want to post it Quote Link to comment Share on other sites More sharing options...
pinkydutta Posted July 22, 2019 Share Posted July 22, 2019 (edited) Yes. Good book! I bought this book a couple of months ago and it was worth it. Really easy to read and good examples, but you need to dig deeper in the code to understand some of the techniques. What helped me a lot was the fact that I read the book after taking that online course from Gustavo Pezzi (from pikuma.com). He even recommends the book in the last session, as one of the suggestions for next steps after the course. I learned a lot from his videos and also from Hugg's book. Edited July 22, 2019 by pinkydutta typos Quote Link to comment Share on other sites More sharing options...
SavedByZero Posted July 23, 2019 Share Posted July 23, 2019 On 7/21/2019 at 10:18 AM, easmith said: posy the entire program please. Or send it to me through messenger if you do not want to post it processor 6502 include "vcs.h" include "macro.h" include "xmacro.h" org $f000 BGColor equ $81 counter equ #0 SpriteHeight equ 9 TooLow equ 5 YPos .byte Start CLEAN_START NextFrame lda #2 sta VBLANK sta VSYNC sta WSYNC sta WSYNC sta WSYNC lda #0 sta VSYNC ldx #37 LVBlank sta WSYNC dex bne LVBlank lda #0 sta VBLANK ldx #192 ;ldy counter lda $5 sta YPos LVScan txa sec sbc YPos cmp #SpriteHeight bcc InSprite lda #0; InSprite tay lda Frame0,y sta WSYNC sta GRP0 lda ColorFrame0,y CUT sta COLUP0 dex bne LVScan ;sta WSYNC ;Playfield section ;lda #255 ; sta PF0 ; lda #135 ; sta PF1 ; lda #135 ; sta PF2 ; lda #2 ; sta COLUBK ; ldy #255 ; sty COLUPF ; clc LVOver sta WSYNC ; dex ; bne LVOver ; dec BGColor ;jmp NextFrame ; Cat-head graphics data Frame0 .byte #0; zero padding, also clears register .byte #%00111100;$AE .byte #%01000010;$AE .byte #%11100111;$AE .byte #%11111111;$AC .byte #%10011001;$8E .byte #%01111110;$8E .byte #%11000011;$98 .byte #%10000001;$98 ; Cat-head color data ColorFrame0 .byte #0; unused (for now) .byte #$AA; .byte #$AC; .byte #$AB; .byte #$AC; .byte #$8E; .byte #$8E; .byte #$98; .byte #$94; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ; Epilogue org $fffc .word Start ; reset vector .word Start ; BRK vector (this was kind of a hybrid of me messing around with some early examples of how to do things) Quote Link to comment Share on other sites More sharing options...
easmith Posted July 23, 2019 Share Posted July 23, 2019 (edited) Try using #5 instead of $5, which is a memory address , a register I think and is probably 0 Edited July 23, 2019 by easmith Quote Link to comment Share on other sites More sharing options...
polyex Posted July 23, 2019 Share Posted July 23, 2019 Just started so it may be a simple answer, but something in that book has me confused. In the book the example puts the vertical blank first , then the vertical sync. This seems backwards to me. From the example on 8bitworkshop.com , the example called 5. Painting on the CRT: NextFrame ; Enable VBLANK (disable output) lda #2 sta VBLANK ; At the beginning of the frame we set the VSYNC bit... lda #2 sta VSYNC ; And hold it on for 3 scanlines... sta WSYNC sta WSYNC sta WSYNC ; Now we turn VSYNC off. lda #0 sta VSYNC ; Now we need 37 lines of VBLANK... ldx #37 LVBlank sta WSYNC ; accessing WSYNC stops the CPU until next scanline dex ; decrement X bne LVBlank ; loop until X == 0 ; Re-enable output (disable VBLANK) lda #0 sta VBLANK ; 192 scanlines are visible ; We'll draw some rainbows ldx #192 lda BGColor ; load the background color out of RAM ScanLoop adc #1 ; add 1 to the current background color in A sta COLUBK ; set the background color sta WSYNC ; WSYNC doesn't care what value is stored dex bne ScanLoop ; Enable VBLANK again lda #2 sta VBLANK ; 30 lines of overscan to complete the frame ldx #30 LVOver sta WSYNC dex bne LVOver Would not this have been correct with VSYNC first? NextFrame ; At the beginning of the frame we set the VSYNC bit... lda #2 sta VSYNC ; And hold it on for 3 scanlines... sta WSYNC sta WSYNC sta WSYNC ; Now we turn VSYNC off. lda #0 sta VSYNC ; Now we need 37 lines of VBLANK... ; Enable VBLANK (disable output) lda #2 sta VBLANK ldx #37 LVBlank sta WSYNC ; accessing WSYNC stops the CPU until next scanline dex ; decrement X bne LVBlank ; loop until X == 0 ; Re-enable output (disable VBLANK) lda #0 sta VBLANK ; 192 scanlines are visible ; We'll draw some rainbows ldx #192 lda BGColor ; load the background color out of RAM ScanLoop adc #1 ; add 1 to the current background color in A sta COLUBK ; set the background color sta WSYNC ; WSYNC doesn't care what value is stored dex bne ScanLoop ; Enable VBLANK again lda #2 sta VBLANK ; 30 lines of overscan to complete the frame ldx #30 LVOver sta WSYNC dex bne LVOver Quote Link to comment Share on other sites More sharing options...
SavedByZero Posted July 24, 2019 Share Posted July 24, 2019 22 hours ago, easmith said: Try using #5 instead of $5, which is a memory address , a register I think and is probably 0 Thanks, but no, that didn’t change anything. In fact I believe I originally had it that way but started messing around, sorry for the confusion. Quote Link to comment Share on other sites More sharing options...
easmith Posted July 24, 2019 Share Posted July 24, 2019 16 hours ago, SavedByZero said: Thanks, but no, that didn’t change anything. In fact I believe I originally had it that way but started messing around, sorry for the confusion. You were missing some things in what you posted: the seg.variables and seg.code definitions. Also , you had your Overscan and VBlank at same time . I added the use of timers for vblank and overscan . This should work ********************************************************************** processor 6502 include "vcs.h" include "macro.h" seg.u variables org $80 YPos .byte seg code org $f000 BGColor equ $81 counter equ 0 SpriteHeight equ $9 TooLow equ $5 ; Cat-head graphics data Frame0 .byte #0; zero padding, also clears register .byte #%00111100;$AE .byte #%01000010;$AE .byte #%11100111;$AE .byte #%11111111;$AC .byte #%10011001;$8E .byte #%01111110;$8E .byte #%11000011;$98 .byte #%10000001;$98 ; Cat-head color data ColorFrame0 .byte #0; unused (for now) .byte #$AA; .byte #$AC; .byte #$AB; .byte #$AC; .byte #$8E; .byte #$8E; .byte #$98; .byte #$94; Start CLEAN_START NextFrame lda #2 sta VSYNC sta WSYNC sta WSYNC sta WSYNC ldx #49 stx TIM64T lda #0 sta VSYNC LVBlank lda INTIM bne LVBlank lda #0 sta VBLANK ldx #192 ;ldy counter lda #5 sta YPos LVScan txa sec sbc YPos cmp #9 bcc InSprite lda #0; InSprite tay lda Frame0,y sta WSYNC sta GRP0 lda ColorFrame0,y CUT sta COLUP0 dex bne LVScan LVOver OverScan ;start Overscan lda #2 sta VBLANK lda #32 sta TIM64T OSwait lda INTIM bne OSwait ; check for end of overscan sta CXCLR jmp NextFrame ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ; Epilogue org $fffc .word Start ; reset vector .word Start ; BRK vector Quote Link to comment Share on other sites More sharing options...
easmith Posted July 24, 2019 Share Posted July 24, 2019 On 7/23/2019 at 1:41 PM, polyex said: Just started so it may be a simple answer, but something in that book has me confused. In the book the example puts the vertical blank first , then the vertical sync. This seems backwards to me. From the example on 8bitworkshop.com , the example called 5. Painting on the CRT: NextFrame ; Enable VBLANK (disable output) lda #2 sta VBLANK ; At the beginning of the frame we set the VSYNC bit... lda #2 sta VSYNC ; And hold it on for 3 scanlines... sta WSYNC sta WSYNC sta WSYNC ; Now we turn VSYNC off. lda #0 sta VSYNC ; Now we need 37 lines of VBLANK... ldx #37 LVBlank sta WSYNC ; accessing WSYNC stops the CPU until next scanline dex ; decrement X bne LVBlank ; loop until X == 0 ; Re-enable output (disable VBLANK) lda #0 sta VBLANK ; 192 scanlines are visible ; We'll draw some rainbows ldx #192 lda BGColor ; load the background color out of RAM ScanLoop adc #1 ; add 1 to the current background color in A sta COLUBK ; set the background color sta WSYNC ; WSYNC doesn't care what value is stored dex bne ScanLoop ; Enable VBLANK again lda #2 sta VBLANK ; 30 lines of overscan to complete the frame ldx #30 LVOver sta WSYNC dex bne LVOver Would not this have been correct with VSYNC first? NextFrame ; At the beginning of the frame we set the VSYNC bit... lda #2 sta VSYNC ; And hold it on for 3 scanlines... sta WSYNC sta WSYNC sta WSYNC ; Now we turn VSYNC off. lda #0 sta VSYNC ; Now we need 37 lines of VBLANK... ; Enable VBLANK (disable output) lda #2 sta VBLANK ldx #37 LVBlank sta WSYNC ; accessing WSYNC stops the CPU until next scanline dex ; decrement X bne LVBlank ; loop until X == 0 ; Re-enable output (disable VBLANK) lda #0 sta VBLANK ; 192 scanlines are visible ; We'll draw some rainbows ldx #192 lda BGColor ; load the background color out of RAM ScanLoop adc #1 ; add 1 to the current background color in A sta COLUBK ; set the background color sta WSYNC ; WSYNC doesn't care what value is stored dex bne ScanLoop ; Enable VBLANK again lda #2 sta VBLANK ; 30 lines of overscan to complete the frame ldx #30 LVOver sta WSYNC dex bne LVOver I don't think you need the lda #2 sta VBLANK at all before you draw your screen if you have it at the bottom of your frame loop for overscan . It remains #2 until you write the #0 after VBLANK. Quote Link to comment Share on other sites More sharing options...
SavedByZero Posted July 24, 2019 Share Posted July 24, 2019 7 minutes ago, easmith said: You were missing some things in what you posted: the seg.variables and seg.code definitions. Also , you had your Overscan and VBlank at same time . I added the use of timers for vblank and overscan . This should work ********************************************************************** processor 6502 include "vcs.h" include "macro.h" seg.u variables org $80 YPos .byte seg code org $f000 BGColor equ $81 counter equ 0 SpriteHeight equ $9 TooLow equ $5 ; Cat-head graphics data Frame0 .byte #0; zero padding, also clears register .byte #%00111100;$AE .byte #%01000010;$AE .byte #%11100111;$AE .byte #%11111111;$AC .byte #%10011001;$8E .byte #%01111110;$8E .byte #%11000011;$98 .byte #%10000001;$98 ; Cat-head color data ColorFrame0 .byte #0; unused (for now) .byte #$AA; .byte #$AC; .byte #$AB; .byte #$AC; .byte #$8E; .byte #$8E; .byte #$98; .byte #$94; Start CLEAN_START NextFrame lda #2 sta VSYNC sta WSYNC sta WSYNC sta WSYNC ldx #49 stx TIM64T lda #0 sta VSYNC LVBlank lda INTIM bne LVBlank lda #0 sta VBLANK ldx #192 ;ldy counter lda #5 sta YPos LVScan txa sec sbc YPos cmp #9 bcc InSprite lda #0; InSprite tay lda Frame0,y sta WSYNC sta GRP0 lda ColorFrame0,y CUT sta COLUP0 dex bne LVScan LVOver OverScan ;start Overscan lda #2 sta VBLANK lda #32 sta TIM64T OSwait lda INTIM bne OSwait ; check for end of overscan sta CXCLR jmp NextFrame ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ; Epilogue org $fffc .word Start ; reset vector .word Start ; BRK vector I will try that, although those header files that I'm missing aren't things I have. They're just....there, in the code sample header that I used as a springboard for my own code. This book is confusing; it doesn't tell me when I'm supposed to be writing new files from sratch vs. just reading the examples to get a feel for them, it doesn't consistently give chapter samples (the chapter I'm trying to recreate the sample for is missing one on the website, where the surrounding chapters both have code samples), and it doesn't explain the header files included that I see in the samples, at least not yet. Quote Link to comment Share on other sites More sharing options...
easmith Posted July 24, 2019 Share Posted July 24, 2019 (edited) 47 minutes ago, SavedByZero said: I will try that, although those header files that I'm missing aren't things I have. They're just....there, in the code sample header that I used as a springboard for my own code. This book is confusing; it doesn't tell me when I'm supposed to be writing new files from sratch vs. just reading the examples to get a feel for them, it doesn't consistently give chapter samples (the chapter I'm trying to recreate the sample for is missing one on the website, where the surrounding chapters both have code samples), and it doesn't explain the header files included that I see in the samples, at least not yet. Yes I know. What is hard to come by, and is frustrating , are complete examples of code in the context of a larger working program . You just have to ask questions. Some experienced programmer will answer. I suggest you start new topic in the 2600 Programming forum for each different technical issue you encounter , so that it gets eyeballs. There are people who are very knowledgeable ( way more than me ). Soon enough you will have a basic template that covers all the the basics that can be duplicated for the most part from program to program . Edited July 24, 2019 by easmith Quote Link to comment Share on other sites More sharing options...
SavedByZero Posted July 24, 2019 Share Posted July 24, 2019 (edited) 54 minutes ago, easmith said: Yes I know. What is hard to come by, and is frustrating , are complete examples of code in the context of a larger working program . You just have to ask questions. Some experienced programmer will answer. I suggest you start new topic in the 2600 Programming forum for each different technical issue you encounter , so that it gets eyeballs. There are people who are very knowledgeable ( way more than me ). Soon enough you will have a basic template that covers all the the basics that can be duplicated for the most part from program to program . Will do, thanks! By the way, I got this code straight from the book: lda #2 ; same as binary #%00000010 sta VBLANK; turn on VBLANK sta VSYNC; turn on VSYNC Now that we’re emitting a VSYNC signal, we need to hold it for three scanlines. We strobe this register (i.e., write to it) to make it halt the CPU until the next scanline begins. If we do this three times, the TIA will have generated our three lines of VSYNC signal and can then turn off the VSYNC bit: sta WSYNC; first scanline sta WSYNC; second scanline sta WSYNC; third scanline lda #0 sta VSYNC; turn off VSYNC Edited July 24, 2019 by SavedByZero Quote Link to comment Share on other sites More sharing options...
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