This shar archive contains a rudimentary disassembler for the Saturn CPU used in the HP48SX (and other HP handhelds), as well as some utility routines. The programs that can be built are: dis48 - disassemble a specified range trace - trace and disassemble starting at an address dobj - disassemble object (incomplete) cvt - convert a memory upload (via memory scanner) to binary file useable by dis48 and trace capture - Macintosh C program to capture memory upload (for use by cvt) from an HP48 in memory scan mode when the SPC key is pressed Makefile - Unix makefile Makefile.mac - Macintosh MPW makefile The programs dis48, trace and dobj share most of the other files. The output is similar to the mnemonics used by Alonzo Gariepy with the following (macro defined) modifications: Hexadecimal numbers have a '$' prefixed. Immediate values have a '#' prefixed. PC-relative instructions have the format: pc+offset (absolute addr) Note that most illegal instructions are probably not noticed. All of these programs are quick hacks, and can undoubtedly stand improvements. The output (on stdout) of the trace program, when started at address 0 results in approximately 80 pages of code discovered by tracing branch and calls as far as possible without emulating the CPU. The error output (on stderr) is a list of addresses that are the targets of call instructions.