| ??? 03/13/05 06:55 Read: times |
#89561 - Random Number Responding to: ???'s previous message |
One way to obtain a pseudo random number in an 8051 type environment is to start up one of the timers. Lets say you need a value between 0 and 99. Setup one of timers in auto reload mode to repeat itself every 100 counts (do not forget to account for the fact that the timer counts up and ends at 255). The timer can be read to find some pseudo random value. Just take the timer value and subtract it from 255 to get the number you want between 0 and 99.
You pick the time to read the timer based upon some event that is not deterministic such as waiting for the user to press a switch. Michael Karas PS....I am mildly amused that you ventured to even guess that this web site would try to hide some secret 8051 opcodes from you. The sum total of the opcodes are shown here on this web page: Opcode Chart MJK |
| Topic | Author | Date |
| Randomization? | 01/01/70 00:00 | |
| No RND op code in 8051/52 | 01/01/70 00:00 | |
| Random Number | 01/01/70 00:00 | |
| random stuff | 01/01/70 00:00 | |
| We can also count.... | 01/01/70 00:00 | |
| But Good Enough!!! | 01/01/70 00:00 | |
| LC RNG | 01/01/70 00:00 | |
| Random what? | 01/01/70 00:00 | |
| maxim's lfsr | 01/01/70 00:00 | |
| the dangers of thinking random is random | 01/01/70 00:00 | |
| wibbly maths | 01/01/70 00:00 | |
| Good old Galois Fields | 01/01/70 00:00 | |
| Bet you didnt know | 01/01/70 00:00 | |
| Try this link | 01/01/70 00:00 | |
| While browsing | 01/01/70 00:00 | |
| rand() | 01/01/70 00:00 | |
| still pseudo | 01/01/70 00:00 | |
| better pseudo! | 01/01/70 00:00 | |
| rand() is part of stdlib.h | 01/01/70 00:00 | |
| true, but not the point | 01/01/70 00:00 | |
application dependent | 01/01/70 00:00 |