Genceli

Mahmut C. Genceli shares here

Among all the things I do, electronics and music are what I like the most. I have been introduced to electricity at a very young age by my father (He was a Linguist and Historian - Prof. Ali Genceli). I was mesmerized watching him change a light switch. When he was not home I took the screwdriver and tried the same. Thankfully he arrived in time to divert my attention to lower voltage devices before I managed to electrocute myself.

Light bulbs and batteries were interesting for a while. I could build a model city and have street lights. The batteries always died quickly. There must have been another way… Later came resistors, capacitors, transistors, … then came building a kit amplifier, building a turntable, MW, LW radio. A few years later I discovered CMOS logic ICs.

I loved logic circuits. I was able to do smarter things with them. Started learning English so I could read foreign electronics magazine articles (Elektor, Wireless World). Using CMOS logic chips I was able to build many projects. Day / Night alarms, strange sounding doorbells, sirens, guitar effects, light modulators, triac controllers, TV effects etc.

I read about a chip called 6502 in Elektor magazine early 80s. A series of articles using 6502 processors was published. Despite I did not understand anything I kept reading. A few years later I bought a Commodore VIC20. I promised myself to use all the commands in the user manual. There were two commands / functions that I could not understand SYS and USR(). The user manual mentioned 6502 chip. The programmers manual for the VIC20 was very difficult to obtain. I connected the dots. Using Elektor's articles, I started poking machine code into the tape buffer area of the VIC20 and voila!!! I was able to make a "*" appear on the screen. 2:00AM in the morning I was very happy. I discovered the magic thing everyone was talking about "The Machine Code". Because I could not get my hands on Commodore's programmers manual; I memorized all the machine code by heart from the table. I tried writing an assembler for VIC20 in BASIC. Ran out of memory before I could tpye all the mnemonics (3.5KB) :). Later I bought a Commodore 64. Rest is history as they say. I got employed as a programmmer, started a computer repair service, started a company designing and manufacturing expansion cards for Commodore 64s, Amigas, PCs, Macs etc.

As my interest in electronics was increasing. I had other teachers that came to mentor me. Senior Engineer from TRT (Turkish Radio Television), Neşet Yılmaztürk, has been very influential. He took me to TRTs electronic labs where they manufactured their circuit boards and equipment. The head technician Şenkal Bey would give me homeworks to build. I used to build them on perf boards. He was always astonished with my ingenious layouts (or the lack of planning).