*** empty log message ***

Makefile

@@ -1,6 +1,20 @@
+#
+# usim CADR simulator
+# $Id$
+#
 
 SRC = main.c decode.c ucode.c
 
+all: usim readmcr
+
 usim: $(SRC)
 	cc -o usim -g $(SRC)
 	./usim >xx
+
+readmcr: readmcr.c
+	cc -o readmcr readmcr.c
+
+clean:
+	rm -f *.o usim readmcr
+
+

README

@@ -0,0 +1,53 @@
+CADR simulator
+8/31/04
+Brad Parker
+[email protected]
+
+What is this?
+-------------
+
+This is a simple hack designed to simulate (emulate?) the CADR
+hardware.  A CADR is a second generation MIT lisp machine.  A good
+description can be found in "A.I. Memo 528" from the MIT AI Labs
+entitled, "CADR".
+
+The CADR was a 32 bit microcoded machine designed to run the lisp
+language.
+
+This program attempts to run the microcode found in the machine
+starting with the "prom" microcode which runs when the machine is
+first powered on.
+
+What state is this in?
+----------------------
+
+The emulation is about 75% done.  It gets pretty far into the prom
+code.  The disk emulation is a hack, but enough to get past the disk
+label code.  The divide code is broken and needs to be fixed.  I think
+most of the ALU code is ok as is the branch and byte code.
+
+The dispatch code is non-existant.  This needs to be added.  I am
+missing page 18 of the CADR memo.  I think this is important for
+dispatch.
+
+What needs to be done?
+----------------------
+
+- fix the divide code
+- create a proper disk emulation (i.e. one which uses a disk image)
+- create a disk image with a real label and a microcode band
+- fill in the dispatch emulation
+
+And most important, find a valid load band.  Without this the emulation
+is uninteresting.  Once we have a load band
+
+- add "tv" emulation
+- add mouse & keyboard emulation
+
+And then we can boot the CADR into the lisp environment.
+
+Long term I want to do some recompiling of the microcode into C and
+assembler, both statically and on-the-fly.  This is the interesting
+part for me :-)
+
+

decode.c

@@ -1,5 +1,9 @@
 /*
  * decode.c
+ *
+ * disassemble CADR microcode
+ * or at least, try to :-)
+ *
  * $Id$
  */
 

readmcr.c

@@ -1,5 +1,10 @@
 /*
  * read cadr .mcr file on a little endian linux box
+ *
+ * just a simple hack to see if we can decode the binary file
+ * before we try to turn it into a microcode band.
+ *
+ * $Id$
  */
 #include <stdio.h>
 #include <fcntl.h>

ucode.c

@@ -4,6 +4,9 @@
  * very brute-force CADR simulator
  * from AIM-528, "CADR"
  *
+ * please remember this is not ment to be fast or pretty.
+ * it's ment to be accurate, however.
+ *
  * Brad Parker <[email protected]>
  * $Id$
  */