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  1. It's from this YouTube tutorial https://www.youtube.com/watch?v=S12qx1DwjVk He shows how to get around using long long. I tried making my own 64bit structure, and it did work but was way to slow for my purposes.
  2. I found some code that works with long int in cc65 guess its 16.16 It just has very limited range #include <stdio.h> #include <stdlib.h> #define scale 16 #define IntToFixed(x) ((x) << scale) #define FixedToInt(x) ((x) >> scale) #define TwoIntToFixed(x,y) IntToFixed(x) + IntToFixed(y)/100 #define FractionPart(x) ((x) & FractionMask) #define WholePart(x) ((x) & WholeMask) #define MUL(x,y) ((((x)>>8)*((y)>>8))>>0) #define DIV(x,y) (((x) << 8 )/ (y) << 8 ) const long FractionMask = (0xffffffff >> (32 - scale)); const long WholeMask = -1 ^ ((0xffffffff >> (32 - scale))); void fprint(long mval){ printf("%ld,%ld\n", FixedToInt(WholePart(mval)), ((FractionPart(mval)*10000))>>16); }
  3. Does anyone have some fixed point code for cc65? Found this https://github.com/PetteriAimonen/libfixmath and tried porting it to cc65, but it uses a lot of 64 bit integers and don't really have the skills to fix that.
  4. I just moved the screen update to a custom interrupt handler and that increased the framerate and audio processing quite a lot.
  5. Yes, sorry, I already changed that a few days ago. But at the time it didn't change anything. I would like to setup a custom IRQ handler but haven't looked into doing that in C. If I disable VSYNC altogether the framerate increases a lot but then the screen is torn. Now my loop is: while(notdone){ //process audio //process input SEI() VSYNC() //update screen CLI() } My Audio loop is: VERA.audio.rate = 0; if(2nd_audio){ while(!(VERA.audio.control & 0x80)){ //while(ii<256){ VERA.audio.data = p[l] + p2[l]; //ii++; l++; if(l > 4095) {l=0;} } } else { while(!(VERA.audio.control & 0x80)){ //while(ii<256){ VERA.audio.data = p[l]; //ii++; l++; if(l > 4095) {l=0;} } } VERA.audio.rate = 64; If I uncomment ii++ there's still some slowdown.
  6. I'm using cc65. Can you declare a variable as zero page in C?
  7. Adding the line int i++ to the audio loop is enough to kill the framerate. Looking at the assembler code the only difference is this snippet: ldy #$08 jsr ldaxysp ina bne L0796 inx L0796: ldy #$07 jsr staxysp ldy #$6A jsr ldaxysp As far as I can tell it just gets the int variable from stack, increases it and stores it again?
  8. I just added -O to my build script and that seems to have fixed the problem. (edit) but then just adding audio_2nd_i++; where audio_2nd_i is an int and the problem is back.
  9. This has the same result. Adder was defined as a char. I think this is most of the audio loop, but don't understand it. jsr _VSYNC ldx #$00 lda #$00 ldy #$61 jsr staxysp jmp L0798 L077F: ldx #$00 lda $9F3B ldx #$00 and #$80 stx tmp1 ora tmp1 jeq L0784 jmp L0780 L0784: ldy #$62 jsr ldaxysp sta regsave stx regsave+1 ina bne L0789 inx L0789: ldy #$61 jsr staxysp lda regsave ldx regsave+1 ldy #$0A lda (sp),y dey ora (sp),y jeq L078A ldy #$05 jsr ldaxysp jsr pushax ldy #$6C jsr ldaxysp jsr tosaddax ldy #$00 jsr ldauidx jsr pushax ldy #$05 jsr ldaxysp jsr pushax ldy #$6E jsr ldaxysp jsr tosaddax ldy #$00 jsr ldauidx jsr tosaddax ldx #$00 sta $9F3D ;write audio jmp L0791 L078A: ldy #$03 jsr ldaxysp jsr pushax ldy #$6C jsr ldaxysp jsr tosaddax ldy #$00 jsr ldauidx sta $9F3D ;write audio L0791: ldy #$6A jsr ldaxysp sta regsave stx regsave+1 ina bne L0797 inx L0797: ldy #$69 jsr staxysp lda regsave ldx regsave+1 ldy #$6A jsr ldaxysp cmp #$00 txa sbc #$10 bvs L079A eor #$80 L079A: asl a lda #$00 ldx #$00 rol a jeq L0798 ldx #$00 lda #$00 ldy #$69 jsr staxysp L0798: ldy #$62 jsr ldaxysp cmp #$00 txa sbc #$01 bvc L0783 eor #$80 L0783: asl a lda #$00 ldx #$00 rol a jne L077F L0780: ldx #$00 lda #$00 ldy #$5B jsr staxysp ldx #$00 lda #$00 ldy #$59 jsr staxysp ldy #$2F jsr ldaxysp ldy #$20 jsr staxysp ldy #$1E jsr ldaxysp sta regsave stx regsave+1 ina bne L07A4 inx L07A4: ldy #$1D jsr staxysp lda regsave ldx regsave+1 lda #$00 jsr _joy_read
  10. Hi I have a core loop where I wait for VSYNC and then update sound and screen. The sound is 8bit mono PCM SEI(); VSYNC(); ii = 0; while(ii < 256){ if((VERA.audio.control & 0x80)){break;} ii++; if(audio_2nd){ adder = p[l] + p2[l]; VERA.audio.data = adder; } else { VERA.audio.data = p1[l];; } l++; if(l > 4095) {l=0; } } When just playing the one sample everything runs fine. But when adding two samples the game/framerate slows down a lot. How can this be when just adding two char values? The screen part of my core loop is scrolling two layers of tiles and one sprite.
  11. I just installed Prog8 and I think it might be helpful. If nothing else it will help me learn the assembly syntax.
  12. I'm trying to port some C code that uses a lot of floating point math, so when I came over the cc65 floatlib I thought my troubles were over. But looking at https://github.com/mrdudz/cc65-floatlib/blob/master/float.inc there seems to be some difference between which calls are used. I would just really like to have the code running before trying to do any assembler optimisations.
  13. Thanks got it working. But it seems you are using another assembler? I could only get it to compile by adding : after definitions. (ie float5_111:) Also the programming reference said to select ROM BANK 4 but that doesn't seem to be necessary? The L1: code was something I found online. Still haven't figured out how to format a float.
  14. That's were my assembly knowledge falls short. My current code is: LDY #$00 L3: LDA mstring,Y CMP #0 BEQ L4 JSR $FFD2 INY JMP L3 L4: How would I change that to an address in A.:.Y ?
  15. As far as I can tell the only address that was different was FOUT. After changing it, my program no longer crashes, but still it doesn't print any characters. The documentation says: fout = $fe81 ; Convert FAC to ASCIIZ string at fbuffr What is "fbuffr"? I know it's a big task. My expertise is in C/C++ But I hope that by gaining a basic understanding of the Float Lib in asm, I might get floatlib to work with x16. Currently I can compile floatlib code, but if I try to actually do something with floats, the program crashes.
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