4 ms·
He talks a bit about the psuedo-random generator [1] they used, including showing some code, but doesn't mention how the seed is set. Given this is an 8088 and
by gregmac 4y ago
He talks a bit about the psuedo-random generator [1] they used, including showing some code, but doesn't mention how the seed is set. Given this is an 8088 and in 1982, I guess there isn't a RTC and they wouldn't use persistent storage for that, so the seed is going to be taken based on startup ticks or something like that -- does anyone know?
If you were to plug in the cabinet and record it, is it going to make the identical sounds every time? (and if not, why not? that implies some external source of randomness)
[1] https://youtu.be/FhkLfz0GKYU?t=1607 https://youtu.be/FhkLfz0GKYU?t=1607
- drfuchs 4y agoWell, the Q*bert Instruction Manual, top of page numbered "17", shows Vbattery powering two "Scratch Pad Memory" RAM chips. This is typically where the "High Scores" are stored in anticipation of your local arcade shutting down for the night; and who knows, maybe the random number seed / state is in there, too. http://pdf.textfiles.com/manuals/ARCADE/K-R/Q-Bert%20(Scan%202)%20[Instructions]%20[English].pdf http://pdf.textfiles.com/manuals/ARCADE/K-R/Q-Bert%20(Scan%2...
- koz1000 4y agoA lot of games I worked on kept a running counter in RAM and then seeded the PRNG when a coin was inserted. That was random enough.