git.y1.nz

commit 8ab2328fa2df7d8af4fc59de68eee4df181050ef
parent cabaee5642b2b779a2049a392f12e790e8744f44
Author: Toxa <56631470+untoxa@users.noreply.github.com>
Date:   Mon, 16 Nov 2020 20:32:50 +0300

Merge pull request #95 from bbbbbr/develop_example_bgb_debug

Examples: Add bgb debug example
Diffstat:
A
gbdk-lib/examples/gb/bgb_debug/Makefile
17
+++++++++++++++++
A
gbdk-lib/examples/gb/bgb_debug/bgb_debug.c
144
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

2 files changed, 161 insertions(+), 0 deletions(-)
diff --git a/gbdk-lib/examples/gb/bgb_debug/Makefile b/gbdk-lib/examples/gb/bgb_debug/Makefile
@@ -0,0 +1,17 @@
+CC	= ../../../bin/lcc -Wa-l -Wl-m -Wl-j -Wm-yc
+
+BINS	= bgb_debug.gb
+
+all:	$(BINS)
+
+make.bat: Makefile
+	@echo "REM Automatically generated from Makefile" > make.bat
+	@make -sn | sed y/\\//\\\\/ | grep -v make >> make.bat
+
+# Compile and link single file in one pass
+%.gb:	%.c
+	$(CC) -o $@ $<
+
+clean:
+	rm -f *.o *.lst *.map *.gb *~ *.rel *.cdb *.ihx *.lnk *.sym *.asm *.noi
+
diff --git a/gbdk-lib/examples/gb/bgb_debug/bgb_debug.c b/gbdk-lib/examples/gb/bgb_debug/bgb_debug.c
@@ -0,0 +1,144 @@
+#include <gb/gb.h>
+#include <stdio.h>      // Just for printf()
+#include <gb/cgb.h>     // Just for the cpu_fast()/slow() calls in CGB 2x example
+
+#include <gb/bgb_emu.h> // Use this include to add the BGB functions
+
+
+// This example shows how to use support for profiling 
+// and logging to the debug window in the BGB emulator.
+//
+// 1. Build this ROM (bgb_debug.gb) then load it in the BGB emulator
+// 2. Open the internal BGB debugger by pressing the "ESC" key
+// 3. From the debugger menu choose "debug messages" to open the debug messages window
+// 4. Reset the gameboy (you may need to press F9 in the debugger to resume running)
+// 5. The debug window will show the BGB messages
+//
+// See the BGB Manual for more information 
+// ("expressions, breakpoint conditions, and debug messages")
+// http://bgb.bircd.org/manual.html#expressions
+
+int main(void)
+{
+    int c;
+
+    SHOW_BKG;
+    DISPLAY_ON;
+    enable_interrupts();
+
+    // Display a message on the GameBoy's screen
+    printf("Message to the \nGameBoy screen\n");
+
+    // Log a message to the BGB debug message window
+    BGB_MESSAGE("Message to the BGB console");
+
+    // ==== Normal Speed Mode ====
+    // Profile code: a single NOP instruction
+    //
+    // In BGB the clock units are "1 nop in [CGB] doublespeed mode".
+    // So when *not* running in CGB doublespeed mode you
+    // have to divide by 2 to get the correct cycle count.
+    //
+    // You should see the message "NOP TIME: 2".
+    //
+    // So in this case, divide the printed value by 2 = The NOP took "1" cycle
+    BGB_MESSAGE("Profile a single NOP instruction at Normal Speed");
+
+    __critical {  // Temporarily turn off interrupts for more accurate measurements
+        BGB_PROFILE_BEGIN();
+            __asm__("nop");
+        BGB_PROFILE_END(NOP TIME);
+    }
+
+
+    // ==== Color Game Boy in Double Speed Mode ====
+    // Profile code: a single NOP instruction
+    //
+    // The BGB_PROFILE_BEGIN/END macros don't support the 
+    // Color Game Boy (CGB) in double speed mode (cpu_fast()).
+    // The example below shows what to use instead (and how to
+    // check for a CGB and turn on Double Speed mode).
+    //
+    // Check and only run this test if on CGB hardware
+    if (_cpu == CGB_TYPE) {
+
+        // Set CGB into double speed mode
+        // (Requires passing -Wm-yc or -Wm-yC with Lcc during build time)
+        cpu_fast();
+        // Set some default DMG styled colors in the CGB Palette
+        cgb_compatibility();
+
+        // In CGB Double Speed mode, you don't have to 
+        // divide by 2 to get the cycle count.
+        //
+        // You should see the message "NOP TIME: 1".
+        BGB_MESSAGE("Profile a single NOP instruction at Double Speed");
+
+        __critical {  // Temporarily turn off interrupts for more accurate measurements
+            BGB_MESSAGE("%ZEROCLKS%");
+                __asm__("nop");
+            // The "-4+" subtracts 4 clocks to compensate for the ones
+            // used by the debug message itself (Normal speed uses -8)
+            BGB_MESSAGE("NOP TIME: %-4+LASTCLKS%");
+        }
+
+        // Return the CGB to normal speed
+        cpu_slow();
+    }
+
+
+    BGB_MESSAGE("Profile code in a loop");
+    __critical {  // Temporarily turn off interrupts for more accurate measurements
+
+        // Profile code in a loop
+        BGB_PROFILE_BEGIN();
+            for(c=0; c<5; c++) {
+                // Do something
+                printf("%d\n", c);
+            }
+        // Elapsed cycle count output is in hex. 
+        // Remember to divide by 2 for the result (Normal Speed)
+        BGB_PROFILE_END(NOP TIME);
+    }
+    
+
+    // ==== Some other things you can print ====
+
+    // TOTALCLKS shows the clocks counter ("internal divider") in the BGB IO map
+    BGB_MESSAGE("Total Clocks: %TOTALCLKS%");
+
+    // CLKS2VBLANK
+    BGB_MESSAGE("Clocks until VBLANK: %CLKS2VBLANK%");
+
+    // Which Banks are currently active (for MBC based cartridges)
+    BGB_MESSAGE("Current  ROM bank: %ROMBANK%");
+    BGB_MESSAGE("Current XRAM bank: %XRAMBANK%");
+    BGB_MESSAGE("Current SRAM bank: %SRAMBANK%");
+    // These are only banked in the CGB
+    BGB_MESSAGE("Current VRAM bank: %VRAMBANK%");
+    BGB_MESSAGE("Current WRAM bank: %WRAMBANK%");
+
+    // Registers (All in this case, or individual ones)
+    BGB_MESSAGE("All Registers: %ALLREGS%");
+
+    // Simple addition with a register
+    BGB_MESSAGE("Register A + 1: %(A+1)%");
+
+    // Read the LY Register a couple times
+    // (Current Y coordinate being rendered to the LCD)
+    BGB_MESSAGE("LY Register (0xFF44): %($ff44)%");
+    BGB_MESSAGE("LY Register (0xFF44): %($ff44)%");
+    // Now print a conditional debug message using it
+    BGB_MESSAGE("Is LY Register > Line 67: %($ff44)>67%Yes;No;");
+
+    // Print some profile info using a built-in function.
+    BGB_MESSAGE("The following lines contain: PROFILE,(SP+$0),(SP+$1),A,TOTALCLKS,ROMBANK,WRAMBANK");
+    BGB_profiler_message();
+    // It's equivalent to:
+    BGB_MESSAGE("PROFILE,%(SP+$0)%,%(SP+$1)%,%A%,%TOTALCLKS%,%ROMBANK%,%WRAMBANK%");
+
+    // The BGB_TEXT() macro will accept a non-quoted string
+    BGB_TEXT(The End);
+
+    return 0;
+}

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