paging tutorial

Makefile

@@ -1,4 +1,10 @@
 compile:
 	png2sp1sprite ./build/cat_sprites.png -i sprite_protar -f 32 > ./build/misifu.asm
-	zcc +zx -v -startup=31 -DWFRAMES=3 -clib=sdcc_iy -Cz--screen=screen.scr -SO3 --max-allocs-per-node200000 @zproject.lst -pragma-include:zpragma.inc -o alley -create-app
-	echo "Done"
+	zcc +zx -v -m -startup=31 -clib=sdcc_iy -SO3 --max-allocs-per-node200000 @zproject.lst -pragma-include:zpragma.inc -o alley
+	ls *.bin
+	appmake +zx -b screen.scr --org 16384 --noloader --blockname screen -o screen.tap
+	appmake +zx -b alley_CODE.bin --org 24500 --noloader --blockname code -o code.tap
+	appmake +zx -b alley_BANK_6.bin --org 49152 --noloader --blockname bank6 -o bank6.tap
+	touch alley.tap
+	rm alley.tap
+	cat loader.tap screen.tap code.tap bank6.tap > alley.tap

README.md

@@ -170,3 +170,33 @@ I'd like to move it move it, ... sure!
      sp1_MoveSprAbs(sp, &full_screen, (void*) 1, 10, 12, 0, 0);
   }
 ```
+
+### How to do paging (128k)
+To be able to page, normal compiling won't be enough so you'll need to create a custom loader.
+
+This loader will be a BASIC PROGRAM, like this loader.bas:
+```
+10 BORDER 0: PAPER 0
+20 CLEAR VAL "24499"
+25 POKE VAL "23739",VAL "111"
+30 LOAD ""SCREEN$
+40 LOAD ""CODE
+45 POKE VAL "23388",VAL "22"
+50 OUT VAL "32765",PEEK VAL "23388"
+60 LOAD ""CODE
+65 POKE VAL "23388",VAL "16"
+70 OUT VAL "32765",PEEK VAL "23388"
+80 RANDOMIZE USR VAL "24500"
+
+```
+
+And then you'll convert the .bin files to real TAP files, and concat them finally in one unique file:
+```
+	appmake +zx -b screen.scr --org 16384 --noloader --blockname screen -o screen.tap
+	appmake +zx -b alley_CODE.bin --org 24500 --noloader --blockname code -o code.tap
+	appmake +zx -b alley_BANK_6.bin --org 49152 --noloader --blockname bank6 -o bank6.tap
+	touch alley.tap
+	rm alley.tap
+	cat loader.tap screen.tap code.tap bank6.tap > alley.tap
+
+```

alley.c

@@ -19,22 +19,26 @@ extern uint8_t sprite_protar4[];
 extern uint8_t cartoon0[];
 
 
-void page(unsigned char bank) {
-//CAUTION BEAUTIFER SCEWS ALL!!!!!
-  if (bank == 0) {
+void show_intro() {
+    /**
+    Switches to BANK 6 and then copies a SCREEN$ file directly to memory
+    */
     __asm
-    ld a, 0xFE
-    ld i, a
+    extern enable_bank_n
+   di
+   ld a,0x80
+   ld i,a                      ; point I at uncontended bank
+
+   ld a,6
+   call enable_bank_n          ; bank 6 in top 16k, stack moved
     __endasm;
-  } else {
+    memcpy(16384, cartoon0, 6900);
     __asm
-    ld a, 0
-    ld i, a
+    extern restore_bank_0
+    call restore_bank_0
+    ei
     __endasm;
-  }
 
-  GLOBAL_ZX_PORT_7FFD = 0x10 + bank;
-  IO_7FFD = 0x10 + bank;
 }
 
 static void initialiseColour(unsigned int count, struct sp1_cs *c)
@@ -62,13 +66,11 @@ struct sp1_ss * add_sprite_misifu() {
 
 int main()
 {
-  intrinsic_di();
-  page(7);
-  memcpy(16384, cartoon0, 6912);
-  page(0);
-  intrinsic_ei();
+  // show paging capabilities.
+  show_intro();
   in_wait_key();
-/*
+
+  // now sp1
   struct sp1_ss* sp = add_sprite_misifu();
   zx_border(INK_WHITE);
 
@@ -83,75 +85,5 @@ int main()
      // sprite, rectangle, offset (animations), y, x, rotationy, rotationx
      sp1_MoveSprAbs(sp, &full_screen, (void*) 1, 10, 12, 0, 0);
      sp1_UpdateNow();
-  }*/
-}
-
-/**
-void page(unsigned char bank) {
-//CAUTION BEAUTIFER SCEWS ALL!!!!!
-  if (bank == 0) {
-    __asm
-    ld a, 0xFE
-    ld i, a
-    __endasm;
-  } else {
-    __asm
-    ld a, 0
-    ld i, a
-    __endasm;
   }
-
-  GLOBAL_ZX_PORT_7FFD = 0x10 + bank;
-  IO_7FFD = 0x10 + bank;
-}
-void game_img( unsigned char *f_img, unsigned char f_page,
-               unsigned char f_lin, unsigned char f_col,
-               unsigned char f_width, unsigned char f_height) {
-
-  unsigned char i;
-  unsigned char *src;
-  unsigned char *dest;
-  unsigned int len;
-  len = f_width * f_height;
-  // 8 x 4 = 32 logo1
-  // Read Draw
-  NIRVANAP_halt(); /// DONT REMOVE CAUSE HANG!!!!
-  intrinsic_di();
-  i = 0;
-  while (i < :heart_eyes: {
-    NIRVANAP_spriteT(i, 0, 0, 0);
-    ++i;
-  }
-
-  src = f_img;
-  page(f_page);
-  dest = &btiles[0];
-  memcpy(dest, src, 48 * len);
-  page(0);
-
-  i = 0;
-  s_col1 = f_col;
-  s_lin1 = f_lin;
-
-  while (i < (len)) {
-    NIRVANAP_drawT_raw(i, s_lin1, s_col1 * 2);
-    ++i;
-    ++s_col1;
-    if ((i % f_width) == 0) {
-      s_lin1 = s_lin1 + 16;
-      s_col1 = f_col;
-    }
-  }
-  intrinsic_ei();
-
 }
-una función page pagina la memoria
-y la otra dibuja la parte que necesitas es
-src = f_img;
-  page(f_page);
-  dest = &btiles[0];
-  memcpy(dest, src, 48 * len);
-  page(0);
-
-
-**/

build/bg.asm

@@ -1,6 +1,61 @@
-SECTION BANK_7_DATA
+SECTION BANK_6
 
 
 PUBLIC _cartoon0
 _cartoon0:
 BINARY "intro.scr"
+
+
+SECTION code_crt_common  ;; place very low in memory, out of top 16k
+
+PUBLIC enable_bank_n
+
+enable_bank_n:
+
+   ; return address
+
+   pop hl
+
+   ; move stack pointer
+
+   ld (temp_sp),sp
+   ld sp,0
+
+   ; enable bank
+
+   and 0x07
+   or 0x10
+
+   ld bc,0x7ffd
+   out (c),a
+
+   ; return
+
+   jp (hl)
+
+temp_sp: defw 0
+
+;
+
+PUBLIC restore_bank_0
+
+restore_bank_0:
+
+   ; return address
+
+   pop hl
+
+   ; restore stack pointer
+
+   ld sp,(temp_sp)
+
+   ; restore bank 0
+
+   ld a,0x10
+
+   ld bc,0x7ffd
+   out (c),a
+
+   ; return
+
+   jp (hl)

loader.bas

@@ -0,0 +1,11 @@
+10 BORDER 0: PAPER 0
+20 CLEAR VAL "24499"
+25 POKE VAL "23739",VAL "111"
+30 LOAD ""SCREEN$
+40 LOAD ""CODE
+45 POKE VAL "23388",VAL "22"
+50 OUT VAL "32765",PEEK VAL "23388"
+60 LOAD ""CODE
+65 POKE VAL "23388",VAL "16"
+70 OUT VAL "32765",PEEK VAL "23388"
+80 RANDOMIZE USR VAL "24500"