XXDP TU58 Boot Loader
While writing and testing my TU58 emulator, I kept running into an odd problem. The boot ROM routines would load the first block from the tape into memory at location 0 and transfer control to this code. The code would begin loading block 9 from the tape, and just as the transfer started, the processor would halt at 0005508 every time. This forced me to disassemble the tape's boot loader. It turns out 0005508 is a halt on checksum error. A halt at 0005468 is a halt on communications error, such as a framing error.
The source code can be found at the link at the bottom of the page. The syntax is in the GNU assember format, so I could assemble and compare the output with the block from the tape.
My disassembler is still a little rough, and not fully tested. One of these days, when I get further along, I plan to make it available.
Resources
- XXDP TU58 boot block source code.
