Differences

This shows you the differences between two versions of the page.

--- base:using_a_running_vice_session_for_development [2016-06-28 20:00] – compyx
+++ base:using_a_running_vice_session_for_development [2016-06-30 14:44] – compyx
@@ Line 141: / Line 141: @@
 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 177: / Line 180: @@
 <code make>
 # x64 binary
-X64 = /usr/local/bin/x64
+X64=/usr/local/bin/x64
+# Assembler
+ASM=64tass
 # Original KERNAL
@@ Line 194: / 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 230: / Line 235: @@
 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 BASIC end-of-program pointer and keyboard buffer.
+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..
-(More coming up, tired)
+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