Hacking the Gibson

When I set out to build my Apple 1 Replica I wanted to recreate the one from the first advertisement. How do you think I did? »

Recently I was bringing up an Apple 1 and I did the first thing I always do to do an initial checkout, which is run the Test Program from the Apple-1 Operation Manual. This is a very simple program that runs a loop that counts from 0x00 to 0xFF and prints each byte as an ASCII character. Here is the program: 0000 LDA #0 0002 TAX 0003 JSR ECHO 0006 INX 0007 TXA 0008 JMP $0002 »

In 1977 Mike Markkula, like many users, was unhappy with the time it took to load data from the cassette interface. He made it a company goal to develop a disk system for the Apple II. After studying the Shugart documentation Woz found that he could avoid much of the complex circuitry needed to control a disk head by doing more work in software. In addition, by doing the board layout himself, Woz was able to reduce chip count even further. »

Recently I wrote an Application for iOS devices that can be used to load Apple 1 software through the cassette interface. One key benefit to this application is that is shows load and verify instructions for each program. I’m currently in the process of getting this added to the App Store. »

Today I built up Mike Willegal’s Apple Cassette Interface for the Apple 1. Previously I was using the Obtronix interface, however Mike’s board is a more accure reproduction. »