From 587df048b8395e12408e88506177fae59aad1124 Mon Sep 17 00:00:00 2001 From: Jeff Parsons Date: Fri, 6 May 2016 08:44:05 -0700 Subject: [PATCH 1/2] C1P assembler README --- pubs/c1p/programming/README.md | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/pubs/c1p/programming/README.md b/pubs/c1p/programming/README.md index 0c188215b..8a556ab19 100644 --- a/pubs/c1p/programming/README.md +++ b/pubs/c1p/programming/README.md @@ -7,4 +7,21 @@ permalink: /pubs/c1p/programming/ Challenger 1P Programming Guides/Samples --- +### 6502 ASSEMBLER/DISASSEMBLER + +This "source code listing" from June 19, 1980 represents the first piece of software I sold, right around the +time I graduated from high school. I had had my Ohio Scientific Challenger 1P for maybe a year when I decided +to write something that would make it easier to write "machine language" programs than the incredibly tedious +HEX monitor that was built into the C1P. And so my **6502 ASSEMBLER/DISASSEMBLER** was born, with full-screen +editor, assembler, and disassembler. + +One of the conditions of the sale, however, was that I provide a "source code" listing. I don't think the buyer +understood that I had essentially written the program in machine language -- because that's how I had to enter it +into the machine. Maybe some lucky C1P users had disk drives and editors and assemblers, but I had none of those +of things. I had never even used tools like that before, which is why the **6502 ASSEMBLER/DISASSEMBLER** is a +bit of an odd duck. I'll post some screenshots and a demo eventually, and you'll see what I mean. + +Anyway, to satisfy the buyer, I sat down at my old manual typewriter and banged out my version of a "source +code" listing. Here it is, many decades later, for your amusement. + [6502 Disassembler Listing (by Jeff Parsons, June 1980)](http://archive.pcjs.org/pubs/c1p/programming/pdfs/OSI_Assembler-Disassembler_Listing.pdf) From 57341d6564555d83493c28fdd9885789eddf3fd2 Mon Sep 17 00:00:00 2001 From: Jeff Parsons Date: Fri, 6 May 2016 08:48:45 -0700 Subject: [PATCH 2/2] C1P assembler README --- pubs/c1p/programming/README.md | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/pubs/c1p/programming/README.md b/pubs/c1p/programming/README.md index 8a556ab19..e6d2b2bbd 100644 --- a/pubs/c1p/programming/README.md +++ b/pubs/c1p/programming/README.md @@ -22,6 +22,7 @@ of things. I had never even used tools like that before, which is why the **650 bit of an odd duck. I'll post some screenshots and a demo eventually, and you'll see what I mean. Anyway, to satisfy the buyer, I sat down at my old manual typewriter and banged out my version of a "source -code" listing. Here it is, many decades later, for your amusement. +code" listing. I produced it mostly by using using the program to disassemble itself, combined with information +from hand-written notes (which I may still have somewhere). Here it is, many decades later, for your amusement. [6502 Disassembler Listing (by Jeff Parsons, June 1980)](http://archive.pcjs.org/pubs/c1p/programming/pdfs/OSI_Assembler-Disassembler_Listing.pdf)