Chuck Peddle, 1937 - 2019

Chuck Peddle, the main designer of the 6502, has passed away on Dec. 15th, 2019. Peddle was one of the engineers that developed the 6800 at Motorola. He later went to MOS in order to implement his vision of an 8bit CPU for way less than $300, which was Motorola’s price for the 6800. This idea of a cheap but powerful CPU materialized as the 6501, and finally the 6502. That very chip, which started the microcomputer revolution, and on which both Marko and myself began to write our first code ever at an early age.
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V9958 - “The WAIT” - investigation of the CPU/VDP /WAIT interface

… on the way back to munich, we had some time to do a little code review of our gfx library. thinking about the cpu to video chip timings and again read the well known datasheets of the V9938/V9958. suddenly i got an enlightenment and we came to the following conclusion. as described in the datasheet (V9958-Technical-manual_v1.0.pdf) of the V9958 there are different timings given for different kind of writes. so as far as we understand there are the following timings
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TMS9929 - Wir wollen was sehen…

… und zwar auf einem Bildschirm! Aber wie stellt man sowas an?! Nun, wir schauen uns um, was Ende der 70-er bzw. Anfang der 80-er Jahre Stand der Technik war und was sich mit überschaubarem Aufwand an eine 6502 CPU “anschließen” lässt. Die Auswahl ist leider überschaubar, denn es sollte irgendwas in DIP maximal noch SDIP sein und dazu noch irgendwie lieferbar - “new old stock”. Wir fanden die TMS9918/28/29-Serie und einige Nachfolger wie den TMS9938/58.
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