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Forum Index : Microcontroller and PC projects : Chuckie Egg for the Pico Computer 3 - the ultimate platform game
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Mixtel90 Guru  Joined: 05/10/2019 Location: United KingdomPosts: 9220 |
I did manage bits of Manic Miner and Lemmings. :) My introduction to Frogger was far older and less complex - Lollipop Lady Trainer on the Nascom-1. I've spent hours and hours on Colossal Cave and Zork though! You make me sound like a real "Gamer". Thanks! :) Mick Zilog Inside! nascom.info for Nascom & Gemini |
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thwill Guru Joined: 16/09/2019 Location: United KingdomPosts: 4405 |
With the exception of Flappy Bird* and Sokoban** I played them all 35+ years ago ;-) * didn't exist ** only discovered from TBS in the last few years If you mean the "Yellow River Kingdom" game that I ported then that is very niche and I suspect only people who had a BBC B would know it. It was one of the edutainment programs on its "Welcome Tape". It is a graphical version of https://en.wikipedia.org/wiki/Hamurabi_(video_game). Best wishes, Tom MMBasic for Linux, Game*Mite, CMM2 Welcome Tape, Creaky old text adventures |
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| matherp Guru Joined: 11/12/2012 Location: United KingdomPosts: 12034 |
One more release of chuckie egg using the original BBC Micro sounds. This needs V6.03.02B6 or above to run chuckie.zip |
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Volhout Guru Joined: 05/03/2018 Location: NetherlandsPosts: 6184 |
Just for clarification: The new chucky egg only runs on 2350 ... correct ? PLAY BBC is not implemented in PicoMite2040VGA .. or is it ? Important to know since the original chucky runs on PicoMite2040VGA. Volhout PicomiteVGA PETSCII ROBOTS |
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| matherp Guru Joined: 11/12/2012 Location: United KingdomPosts: 12034 |
It is implemented in all builds including PICOMIN |
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| Volhout Guru Joined: 05/03/2018 Location: NetherlandsPosts: 6184 |
Peter, On picomite2040VGA (running b6) there is one thing strange. I run the demo you included with the elite sounds. Sound number 2 (explosion noise) is not audible (silent) but... After finishing sound number 9 (the last one) the noise of the explosion is heard. (when the text shows that sounds of explosion are combined). But not audible as individual noise half. Volhout P.S. maybe related : in the first picomite chucky there was a 'footsteps' sound when walking. In the new chucky there is only a constant dit-dit sound, but no footsteps. And the dit-dit is not related to walking. Maybe this is per design, as I do not know the game. Edited 2026-09-16 19:27 by Volhout PicomiteVGA PETSCII ROBOTS |
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| matherp Guru Joined: 11/12/2012 Location: United KingdomPosts: 12034 |
Fixed Chuckie Egg sound chuckie.zip The sound demo is correct. Both are silent by design, for two different reasons — neither is a fault in the demo or in the firmware. #2, "explosion, the noise half" — channel 0, pitch 7. Pitch 7 is white noise clocked by channel 1, not at one of the three fixed rates. The engine takes the clock from channel 1's phase increment (io/AudioBBC.c:404-411): int tuned = ((np & 3) == 3); if (!tuned || b->ch[1].inc) At that point in the demo channel 1 has never been given a note — sounds 0 and 1 are channel word 18, i.e. channel 2. So ch[1].inc is still 0, there is nothing to clock the shift register with, and the guard deliberately emits nothing rather than parking the LFSR at a DC level for 1.3 seconds. The comment just above it says exactly that: "Until channel 1 has a pitch there is nothing to be tuned by, and those two settings stay silent." On a real BBC you would get whatever junk was left in the tone-1 period register, so the noise half alone was never a defined sound there either. You can prove it: play #3 first and then #2 (channel 1's increment survives the note), and #2 will hiss. #3, "the tone that sweeps it" — channel 1, amplitude 3 = envelope 3. Envelope 3's ADSR is AA=1, AD=0, AS=0, AR=-1, ALA=1, ALD=1. Attack adds 1 per step and immediately hits the attack target level of 1; decay of 0 leaves it at the decay level, also 1; sustain adds 0. So the note sits at level 1 out of the 126 the engine scales (io/AudioBBC.c:214-240) — about −42 dB, and after the mix *= 64 an amplitude of 64 in a ±32767 sample. It is inaudible on purpose. Elite's envelope 3 exists for its pitch half (240 sweeping down through PI1/PI2/PI3), whose only job is to clock the noise on channel 0. On a real BBC it would be even more thoroughly silent: the OS maps the 0–126 level onto the SN76489's 4-bit volume, and 1 rounds to off. Which is why the pair at the end of your demo is the only way either of them is meant to be heard — the tone tunes and sweeps, the noise is what you actually hear, and the demo's own comment ("Heard apart, neither is the sound") is correct. |
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