SFML and PN noise (8-bit emulation) -


i have had absurd idea write commodore vic-20 emulator, first computer.

everything has gone quite until sound emulation time has come! vic-20 has 3 voices (square waveform) , noise speaker. searching net found pn generator (somewhere called "white" noise).

i know white noise not frequency driven, put specific frequency value noise register (poke 36877,x command). formula is:

freq = cpu_speed/(127 - x)

(more details on vic-20 programmer's guida, mos6560/6561 vic-i chip)

where x 7-bit value of noise register (bit 8 noise on/off switch)

i have 1024 pre-generated buffer of numbers (the pseudo-random sequence), question is: how can correlate frequency (freq) create sample buffer pass sound card (in case sf::soundbuffer accepts sf::int16 (aka unsigned short) values?

i guess of had commodore vic-20 or c64 @ home , played old poke instruction... can of me in understanding step?

edit:

searching on internet found c64 programmer's guida shows waveform graph of noise generator. can recognize kind of wave/perturbation etc...? waveform seems periodic (with period of freq), how tu generate such wave?

c64 noise waveform


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