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In the middle 80’s of the last century my father bought a Phillips NMS8250 MSX2 computer. This computer was better in any respect that the TRS-80 computer we already head...except for one thing: it had no Instant Assembler like the TRS-80 had.

Instant Assembler was a combined Assembler/Debugger/Disassembler for the TRS-80 by Mumford Micro Systems. It was a very interactive and productive way to create powerfull programs in Z-80 assembly. As a teenager I learnt to program Z-80 machinecode programs thanks to Instant Assembler.

I tried assemblers for the MSX, but they just made everything complex and slow. OK, maybe forst assembling an then linking object files was the right way to create complex programs. But it made life mostly slow and inproductive.

So what did I do? I just built my own kind of Instant assembler for the MSX2. I actually created the first version on the TRS-80 using Instant Assembler. At a certain point my own assembler was able to process its own source code, that was the moment I transferred the program to our MSX computer using an RS232 connection. After that I transferred the source code. And finally I had my assembler create it’s own executable on the MSX!

At a certain day in 1987 I met mr Ragas from Terminal Software Publications while visiting a hobby computer fair. I told him about my own assembler, and he showed interrest to publish it. We came to an agreement, and I had to make up a name for my assembler. It was Really Fast, so I called it RF-ASSEMBLER. Of course RF are my initials, this was not by accident.

Given the fact that is heavily inspired by Instant Assembler there are some incompatibilities with source code from other contemporary assemblers, like upper/lowercase dependencies and colons after label definition. But for interactie software development and debugging that's no issue.

Currently Terminal Software Publications no longer exists. I tried to locate them, but I can’t track them down. Assuming that they no longer exist, I think nobody objects to me open sourcing RF-ASSEMBLER. The alternative is to leave the floppies containing te software catch dust while deteriorating until they can no longer be read.

So here it is: RF-ASSEMBLER. Both the assembler and its source code. I can imagine there's no need for RF-ASSEMBLER on MSX2 any more, but it may be useful on other (retro) Z-80 systems. It may need tweaking, but that's what the source code is useful for.

The software includes a brief manual, so it can be used on an (emulated) MSX2 system. Some additional documentation that might be useful is the manual of Mumford’s Instant Assembler because that’s what RF-ASSEMBLER is inspired by. This documentation can be found on the internet in the form of scans of the manual.








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