#ifdef'ed out code passages that do not fit the m5484LITE board

BaS_gcc/sources/exceptions.S

@@ -21,6 +21,11 @@
  */
 
 #include "startcf.h"
+#if MACHINE_FIREBEE
+#include "firebee.h"
+#elif MACHINE_M5484LITE
+#include "m5484l.h"
+#endif /* MACHINE_FIREBEE */
 
 		.extern __Bas_base
 		.extern __SUP_SP
@@ -215,18 +220,24 @@
 		move.w	#0x2700,sr			// disable interrupt
 		subq.l	#8,a7
 		movem.l	d0/a5,(a7)			// save registers
+
 		lea		MCF_EPORT_EPFR,a5
 		move.b	#\clr_int,(a5)		// clear int pending
-// test auf protect mode ---------------------
+
+#if MACHINE_FIREBEE
+// test for protect mode. Only for FireBee (m5484LITE has no dip switch)
 		move.b	DIP_SWITCHa,d0
 		btst	#7,d0 
-		bne		irq_protect			// ja->
+		bne		irq_protect			// yes
-// -------------------------------------------		
+#endif /* MACHINE_FIREBEE */
+
 		movem.l	(a7),d0/a5			// restore registers
 		addq.l	#8,a7
 		move.l	\vector,-(a7)
 		move	#0x2\int_mask\()00,sr
 		rts
+
+#if MACHINE_FIREBEE
 irq_protect:
 		move.l	usp,a5				// get usp
 		tst.b	_rt_mod				// supervisor mode active?
@@ -253,7 +264,7 @@ sev_supint:
 		move.l	12(a7),-(a5)		// pc verschieben
 		move.w	10(a7),-(a5)		// sr verschieben
 		bset	#5,(a5)				// auf super
-#endif
+#endif /* cf_stack */
 irq_end:
 		move.l	a5,usp				// usp setzen
 		lea		\vector,a5
@@ -263,6 +274,7 @@ irq_end:
 		movem.l	(a7),d0/a5			// register zur<EFBFBD>ck
 		addq.l	#8,a7
 		rte							// und weg 
+#endif /* MACHINE_FIREBEE */
 		.endm
 
 /*
@@ -280,9 +292,9 @@ irq_end:
  * If anybody knows of any better way on how to do this - please do!
  *
  */
-    .macro mchar  st,a,b,c,d,tgt
+    	.macro mchar  st,a,b,c,d,tgt
-    \st #\a << 24|\b<<16|\c<<8|\d,\tgt
+    		\st #\a << 24|\b<<16|\c<<8|\d,\tgt
-    .endm
+    	.endm
 
 .text
 _vec_init:
@@ -304,16 +316,23 @@ init_vec_loop:
 		subq.l	#1,d0
 		bne		init_vec_loop
 
-		move.l	#__SUP_SP,(a0)
+		move.l	#__SUP_SP,(a0)		// set initial stack pointer at start of exception vector table
-		lea		reset_vector(pc),a1
+
+		lea		reset_vector(pc),a1	// set reset vector
 		move.l	a1,0x04(a0)
-		lea		acess(pc),a1
+
+		lea		access(pc),a1		// set illegal access exception handler
 		move.l	a1,0x08(a0)
 		
+#ifdef MACHINE_FIREBEE	/* only the FireBee has a dip switch */
 		move.b	DIP_SWITCHa,d0		// ++ vr
 		btst	#7,d0 
 		beq		no_protect_vectors
+#elif MACHINE_M5484LITE
+		bra		no_protect_vectors
+#endif /* MACHINE_FIREBEE */
 		
+#ifdef MACHINE_FIREBEE	/* protect mode only enabled for FireBee */
 		lea		_illegal_instruction(pc),a1
 		move.l	a1,0x0c(a0)
 		lea		_illegal_instruction(pc),a1
@@ -347,15 +366,18 @@ init_vec_loop:
  		lea		flpoow(pc),a1
   		move.l	a1,0xdc(a0)
 
+#endif /* MACHINE_FIREBEE */
+
 
 no_protect_vectors:
 		
-		// trap #0 (without any parameters for now) is used to provide BaS' XHDI
+// trap #0 (without any parameters for now) is used to provide BaS' XHDI
-		// routine address to EmuTOS.
+// routine address to EmuTOS.
 		lea		_xhdi_sd_install,a1
 		move.l	a1,0x80(a0)				// trap #0 exception vector
 
 // ACP interrupts 1-7 (user-defined, generated by FPGA)
+// TODO: Do we need to do anything special for m5484LITE here?
 		lea		irq1(pc),a1
 		move.l	a1,0x104(a0)
 		lea		irq2(pc),a1
@@ -370,14 +392,21 @@ no_protect_vectors:
 		move.l	a1,0x118(a0)
 		lea		irq7(pc),a1
 		move.l	a1,0x11c(a0)
-// PSC vectors
+
+/*
+ * m5448LITE has neither PIC nor emulated VIDEL, so we do nothing special for it here which keeps the
+ * std_exc_vec in place we set earlier
+ */
+#ifdef MACHINE_FIREBEE
+// install PSC vectors (used for PIC communication on the FireBee)
 		lea		handler_psc3(pc),a1
 		// PSC3 interrupt source = 32
 		move.l	a1,(INT_SOURCE_PSC3 + 64) * 4(a0)
-// timer vectors
+// timer vectors (used for video page copy on the FireBee)
 		lea		handler_gpt0(pc),a1
 		// GPT0 interrupt source = 62
 		move.l	a1,(INT_SOURCE_GPT0 + 64) * 4(a0)
+#endif /* MACHINE_FIREBEE */
 
 		move.l	(sp)+,a2			// Restore registers
 		rts
@@ -390,9 +419,11 @@ std_exc_vec:
 		subq.l	#8,a7
 		movem.l	d0/a5,(sp)			// save registers
 
+#ifdef MACHINE_FIREBEE
 		move.b	DIP_SWITCHa,d0		// "protect mode"?
 		btst	#7,d0 
 		bne		stv_protect			// yes
+#endif /* MACHINE_FIREBEE */
 
 		move.w	8(sp),d0			// fetch vector
 		and.l	#0x3fc,d0			// mask out vector number
@@ -409,6 +440,7 @@ std_exc_vec:
 		move.l	(a7)+,d0			// restore d0
 		rts							// jump to exception routine
 
+#ifdef MACHINE_FIREBEE
 stv_protect:
 		move.l	usp,a5				// usp holen  
 		tst.b	_rt_mod				// supervisor? 
@@ -435,6 +467,7 @@ stv_protect:
 		movem.l	(a7),d0/a5			// register zur<EFBFBD>ck
 		addq.l	#8,a7
 		rte							// und weg 
+
 sev_sup:
 #ifdef cf_stack
 		move.l	12(a7),-(a5)		// pc transferieren 
@@ -457,7 +490,8 @@ sev_sup:
 		movem.l	(a7),d0/a5			// register zurück
 		addq.l	#8,a7
 		rte							// und weg 
-//*******************************************
+#endif /* MACHINE_FIREBEE */
+
 reset_vector:
 		move.w	#0x2700,sr			// disable interrupt
 		move.l	#0x31415926,d0
@@ -465,10 +499,11 @@ reset_vector:
 		beq		std_exc_vec			// yes->
 		jmp		_rom_entry	 		// no, cold start machine
 
-acess:
+access:
 		move.w	#0x2700,sr			// disable interrupt
 		move.l	d0,-(sp)			// ++ vr
-		move.w	4(sp),d0
+
+		move.w	4(sp),d0			// get format_status word from stack
 		andi.l	#0x0c03,d0			// mask out fault status bits
 		cmpi.l	#0x0401,d0			// TLB miss on opword of instruction fetch?
 		beq		access_mmu			// yes
@@ -484,6 +519,7 @@ access_mmu:
 		move.l	MCF_MMU_MMUSR,d0	// did the last fault hit in TLB?
 		btst	#1,d0				// no
 		bne		bus_error			// bus error handler
+
 		move.l	MCF_MMU_MMUAR,d0
 		cmp.l	#__FASTRAM_END,d0	// above max User RAM area?
 		bge		bus_error			// -> bus error