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--- base:using_a_running_vice_session_for_development [2016-06-28 19:39] – compyx
+++ base:using_a_running_vice_session_for_development [2016-06-30 14:44] – compyx
@@ Line 139: / Line 139: @@
 </code>
-Again, this becomes tedious, having to type this again and again, so we update our Makefile:
+Again, this becomes tedious, having to type this again and again, so we update our Makefile (just the new parts for now):
 <code make>
+ASM=64tass
 # Default make target: just assemble the program:
 all: demo.prg
@@ Line 147: / Line 150: @@
 # Assemble program
 demo.prg: demo.s
-        $(X64) -a -C -o demo.prg demo.s
+        $(ASM) -a -C -o demo.prg demo.s
@@ Line 161: / Line 164: @@
 The `-q 1` argument to netcat is required to allow the reset to properly finish. netcat does not wait for VICE to complete its task, it immediately exits on EOF, so we use `-q 1` to tell netcat to wait one second after EOF. You could also use `sleep 1` after issuing 'reset 0', it has the same effect (adjust to sleep 3 when using a non-patched KERNAL).
+Since the 'run' target depends on 'demo.prg', that file automatically gets (re)built whenever we issue `make run`, and when the building fails no data is inserted into VICE.
 === Loading labels into VICE ===
@@ Line 171: / Line 177: @@
 Again giving VICE time to process the 'clear_labels' command before sending the 'load_labels' command. Obviously not needed when issuing these commands from the shell, but using a Makefile, this is required.
-So, lets update our Makefile once again:
+So, lets update our Makefile once again (full Makefile now):
 <code make>
 # x64 binary
-X64 = /usr/local/bin/x64
+X64=/usr/local/bin/x64
+# Assembler
+ASM=64tass
 # Original KERNAL
@@ Line 191: / Line 199: @@
 # Assemble program and output VICE labels file
 demo.prg: demo.s
-        $(X64) -a -C -o demo.prg demo.s --vice-labels -l labels.txt
+        $(ASM) -a -C -o demo.prg demo.s --vice-labels -l labels.txt
@@ Line 208: / Line 216: @@
 # Start VICE session with remote monitor and patched KERNAL in the background
+# redirecting VICE's output to a black hole
 session: $(KERNAL_PATCHED)
         $(X64) -remotemonitor -kernal $(KERNAL_PATCHED) \
@@ Line 218: / Line 227: @@
         rm -f $(KERNAL_PATCHED)
 </code>
+There you have it, running and debugging code with a live VICE session, avoiding a lot of start up time. Unfortunately, when using this for code that **doesn't** set up IRQ's, we have a little problem.
+== Proper BASIC initialization ==
+Since we bypass the C64's OS (the BASIC interpreter), when we execute code using the above method, the C64 doesn't know we executed a program and keeps the IRQ of the interpreter running, resulting in a nice blinking cursor.
+So we need a way to do a proper 'RUN' after injecting our program. We can do this with a simple SYS line and some tweaking of the <del>BASIC end-of-program pointer and</del> keyboard buffer.
+Let's assume our demo.s looks like this:
+<code 64tass>
+        * = $0801
+        ; BASIC section: this becomes "2016 sys2061"
+        .word (+), 2016
+        .null $9e, ^start
++       .word 0
+start   ; this is $080d
+        lda #0
+        sta $d020
+        sta $d021
+        rts
+</code>
+When we run this using the Makefile shown, the border and background turn black, but we get a blinking cursor. So we need to somehow force BASIC to properly run this SYS line. This can be done with a little tweaking:
+(Thanks to Groepaz for coming up with the suggestion of simply putting 'RUN' into the keyboard buffer!)
+First we load the binary into VICE, then we set the end-of-basic pointer to $080d, fill the keyboard buffer with "RUN\r" and let the magic happen:
+<code bash>
+# reset, and wait, otherwise the BASIC start-of-basic pointer gets overwritten to $0000 while loading
+echo 'reset 0' | netcat -q 1 localhost 6510
+# load binary
+echo 'l "demo.prg" 0' localhost 6510
+# put 'RUN\r' into the keyboard buffer
+echo 'f 0277 027a 52 55 4e 0d' | netcat localhost 6510
+# set keyboard buffer size to $04 -> strlen("RUN\r")
+echo 'f 00c6 00c6 04' | netcat localhost 6510
+</code>
+Putting this in our Makefile, we end up with this:
+<code make>
+# x64 binary
+X64 = /usr/local/bin/x64
+# Assembler
+ASM=64tass
+# Original KERNAL
+KERNAL=/usr/lib/vice/C64/kernal
+# Patched KERNAL
+KERNAL_PATCHED=kernal-quick-memtest
+# Generate patched KERNAL for faster reset (skip BASIC memtest)
+$(KERNAL_PATCHED): $(KERNAL)
+	cp $(KERNAL) $(KERNAL_PATCHED)
+	echo "1d69: 9f" | xxd -r - $(KERNAL_PATCHED)
+all: demo.prg
+# Assemble program and output VICE labels file
+demo.prg: demo.s
+        $(ASM) -a -C -o demo.prg demo.s --vice-labels -l labels.txt
+# Inject program into VICE session and run it
+run: demo.prg
+        # we need to wait one second for the reset to finish, so we use -q 1
+        echo 'reset 0' | netcat -q 1 localhost 6510
+        # clear and (re)load labels
+        echo 'clear_labels' | netcat -q 1 localhost 6510
+        echo 'load_labels "labels.txt"' | netcat localhost 6510
+        # load demo.prg from the virtual FS, our host OS
+        echo 'l "demo.prg 0"' | netcat localhost 6510
+        # put 'RUN\r' into the keyboard buffer
+        echo 'f 0277 027a 52 55 4e 0d' | netcat localhost 6510
+        # set keyboard buffer size to $04 -> strlen("RUN\r")
+        echo 'f 00c6 00c6 04' | netcat localhost 6510
+# Start VICE session with remote monitor and patched KERNAL in the background
+# redirecting VICE's output to a black hole
+session: $(KERNAL_PATCHED)
+        $(X64) -remotemonitor -kernal $(KERNAL_PATCHED) \
+                > /dev/null 2>&1 &
+# Clean up
+.PHONY: clean
+clean:
+        rm -f demo.prg
+        rm -f $(KERNAL_PATCHED)
+</code>
+More later..
+TODO:
+  * attaching disk images
+  * debugging via telnet
+  * writing a proper Makefile (perhaps putting all those echo's into a file, updating it with sed)
+  * VIM integration