added a way to create Ultimate64 based hybrid ROM

Makefile

@@ -471,6 +471,18 @@ build/kernal_hybrid.rom: kernal $(DIR_GEN)/OUTK_x.BIN
 build/symbols_hybrid.vs: $(DIR_GEN)/KERNAL_combined.vs
 	@sort $(DIR_GEN)/KERNAL_combined.vs | uniq | grep -v "__" > $@
 
+build/kernal_hybrid_u64.rom: kernal $(DIR_U64)/OUTK_x.BIN
+	@echo
+	@echo $(HYBRID_WARNING)
+	@echo
+	(dd if=kernal bs=1140 count=1 skip=0        ; \
+	echo "    > HYBRID ROM, DON'T DISTRIBUTE <" ; \
+	dd if=kernal bs=1 count=58 skip=1176        ; \
+	cat $(DIR_U64)/OUTK_x.BIN) > $@
+
+build/symbols_hybrid_u64.vs: $(DIR_U64)/KERNAL_combined.vs
+	@sort $(DIR_U64)/KERNAL_combined.vs | uniq | grep -v "__" > $@
+
 # Rules - MEGA65 platform specific
 
 build/padding_64_KB:
@@ -563,6 +575,15 @@ test_hybrid: build/kernal_hybrid.rom build/symbols_hybrid.vs
 	@echo $(HYBRID_WARNING)
 	@echo
 
+test_hybrid_u64: build/kernal_hybrid_u64.rom build/symbols_hybrid_u64.vs
+	@echo
+	@echo $(HYBRID_WARNING)
+	@echo
+	x64 -kernal build/kernal_hybrid_u64.rom -moncommands build/symbols_hybrid_u64.vs -1 $(TESTTAPE) -8 $(TESTDISK)
+	@echo
+	@echo $(HYBRID_WARNING)
+	@echo
+
 test_m65: build/mega65.rom
 	m65 -b ../mega65-core/bin/mega65r1.bit -k ../mega65-core/bin/KICKUP.M65 -R build/mega65.rom -4
 

bin/README.md

@@ -6,8 +6,8 @@ Follow these rules, or bad things will happen!
 
 * Don't mix these ROMs with any other ROMs; exceptions:
 
-   - kernal_hybrid.rom, which is meant to be used (and has to be used) with the original BASIC ROM;
+   - kernal_hybrid\*.rom, which is meant to be used (and has to be used) with the original BASIC ROM;
-     however, this hybrid ROM cannot be distributed due to legal/copyright reasons; see [here](./../doc/Hybrid-build.md) for instruction how to create it
+     however, these hybrid ROMs cannot be distributed due to legal/copyright reasons; see [here](./../doc/Hybrid-build.md) for instruction how to create them
 
    - chargen_*.rom - these ones are fully interchangeable
 

doc/Hybrid-build.md

@@ -3,7 +3,9 @@ The C64 ROM is typically distributed in 2 files 8 KB each, one called *kernal*,
 
 But it is still possible to combine them:
 * copy the *kernal* file to the *open-roms* main directory
-* from the Linux command line type `make test_hybrid` - this will crate the hybrid Kernal file, *open-roms/bin/kernal_hybrid.rom*, and launch VICE emulator with it
+* from the Linux command line type `make test_hybrid` on `make test_hybrid_u64` (for Ultimate 64 based Kernal build- this will crate the hybrid Kernal file, *open-roms/bin/kernal_hybrid.rom* or *open-roms/bin/kernal_hybrid_u64.rom*, and launch VICE emulator with it
+
+Unfortunately, some features will be lost this way - for example, the Open ROMs DOS Wedge is BASIC based, so it won't be available in the hybrid ROM.
 
 Sorry, no Windows support (but it should work under *Windows Subsystem for Linux* if GCC and libpng devel packages are installed), and no macOS support (I don't have a machine to test).