Search found 488 matches
- 24 May 2018, 18:47
- Forum: Hardware and software hacking
- Topic: MIDI Audio:
- Replies: 18
- Views: 12940
Re: MIDI Audio:
I have the nagging feeling that the low-pitch noise might be caused by the mismatch between 521 scan lines and 4 sound channels. Every 16.7 ms there will be an interval of 5, not 4, scan lines that are together producing a sample. That can and will overflow. The solution I had in mind is that the vi...
- 23 May 2018, 23:08
- Forum: Kit assembly gallery
- Topic: Sockets for the ICs
- Replies: 10
- Views: 11580
Re: Sockets for the ICs
Could you elaborate a little about which problems may I expect if using sockets? Mechanically it needs more care. It is easier to bend or break a pin on insert, or miss that a pin is not inserted at all but dangling on the side. It is much simpler to put an IC directly into the PCB without errors t...
- 23 May 2018, 18:23
- Forum: Hardware and software hacking
- Topic: Extending the Gigatron instruction set
- Replies: 22
- Views: 16989
Re: Extending the Gigatron instruction set
More ideas to win speed for your Hackatron Grand Master (HGM):
- Hookup a different type of output device so you don't need to worry about VGA signals (LCD or OLED display with I2C or SPI)
- Faster chips
- 23 May 2018, 17:42
- Forum: Hardware and software hacking
- Topic: About GitHub repositories
- Replies: 3
- Views: 3855
Re: About GitHub repositories
Contrib/ it is!
- 23 May 2018, 16:36
- Forum: Hardware and software hacking
- Topic: Where to find the emulator?
- Replies: 8
- Views: 6486
Re: Where to find the emulator?
Phil's is also live on the web page under "Home": https://gigatron.io/ It works fine with Chrome and Firefox, but there seems to be an issue with Safari. We also have Martin's that is listed under "Tutorials", bottom of the page: https://gigatron.io/?page_id=574 This is the one w...
- 22 May 2018, 14:46
- Forum: Hardware and software hacking
- Topic: About GitHub repositories
- Replies: 3
- Views: 3855
About GitHub repositories
at67 has extensive developments in his fork of gigatron-rom. There are other people doing similar things as well. Those developments are largely orthogonal to what is already there and I see two ways we can go with this: 1. Keep independent developments separate in independent trees. Reject the pull...
- 22 May 2018, 10:24
- Forum: Hardware and software hacking
- Topic: MIDI Audio:
- Replies: 18
- Views: 12940
Re: Midi Audio:
keyL:keyH -- 15-bit frequency (bit7 of keyL should be 0). There is a lookup table on page 7 in ROM oscL:oscH -- 15-bit phase, automatically incremented with keyL:keyH every 4 scan lines (1 channel per scan line) wavX -- Modulation of index with XOR operation wavA -- Modulation after table lookup wit...
- 21 May 2018, 19:59
- Forum: Hardware and software hacking
- Topic: Blue LEDs for Power and Blinkenlights
- Replies: 5
- Views: 5574
Re: Blue LEDs for Power and Blinkenlights
I've blown a few that way judging from my damaged parts jar.
- 21 May 2018, 16:52
- Forum: Hardware and software hacking
- Topic: MIDI Audio:
- Replies: 18
- Views: 12940
Re: Midi Audio:
We knew we were not going to get anywhere near the MOS 6581 of course, but this is GREAT beeping! Indeed, setting the key to 0 Hz acts as OFF for the channel. With that, the soundTimer control variable is merely a convenience for simpler programs. It is a minor inconvenience if you don't want it to ...
- 21 May 2018, 13:41
- Forum: Hardware and software hacking
- Topic: Blue LEDs for Power and Blinkenlights
- Replies: 5
- Views: 5574
Re: Blue LEDs for Power and Blinkenlights
In the Ben Eater series you can see the he doesn't use resistors. That is a bit of a poor practice, but he gets away with it because he has older 74LS chips that don't deliver much current in the first place. And probably his LEDs need a lot and he uses a juicy USB charger. With the chips in the kit...