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Can anyone confirm the frequency the C64 CIA 16bit timers tick per second ?

mP.
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1 Answers1

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In the C64, the 6526/8521 CIA chips run at the phase 2 system clock rate, which is set at either 0.985248MHz (PAL) or 1.022727Mhz (NTSC).

Eight-Bit Guru
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  • i suspected this but couldnt confirm :) thanx! – mP. May 08 '12 at 11:11
  • The 6526 datasheet is here, for further detailed information: http://archive.6502.org/datasheets/mos_6526_cia.pdf (don't forget to accept the answer if it resolved your query). – Eight-Bit Guru May 08 '12 at 11:21