Search found 25 matches
- 14 Jul 2018, 20:48
- Forum: Hardware and software hacking
- Topic: High resolution mode?
- Replies: 38
- Views: 39012
Re: High resolution mode?
I'm thinking to get both the high-res and low-res modes, we could add a 2:1 analog multiplexer: 74HCT4053. We'd need two different resistor arrays, but this would be a simple solution. Then we could pull a line from the blinkenlights to the select line. OR as a more advanced option - we could captur...
- 13 Jul 2018, 13:58
- Forum: Hardware and software hacking
- Topic: Extending the Gigatron instruction set
- Replies: 22
- Views: 16969
Re: Extending the Gigatron instruction set
What about something a little less intrusive? I'd hate to become incompatible with the current instruction set with all of the work people are doing developing the software. What if we just replace the instructions which are currently unusable? Specifically, the store instructions which write to RAM...
- 10 Jul 2018, 23:26
- Forum: Hardware and software hacking
- Topic: High resolution mode?
- Replies: 38
- Views: 39012
Re: High resolution mode?
Yes with 6 color outputs per 1 pixel we could reduce it to 3 color outputs per 2 pixels. It's still a color reduction when going to 320 pixels, but probably worth it to get to 40 characters per row for a text mode. It may still work with an asymmetric clock. It depends on when the VGA monitor sample...
- 10 Jul 2018, 17:08
- Forum: Hardware and software hacking
- Topic: High resolution mode?
- Replies: 38
- Views: 39012
High resolution mode?
I was thinking of ways to increase the resolution video output. Right now it takes one instruction per pixel, so you can't really optimize that. But I was thinking what if did two pixels per instruction? Maybe if we do a DDR (double-data-rate) trick by putting a 2:1 mux on the OUTPUT with the clock ...
- 27 Jun 2018, 13:01
- Forum: Hardware and software hacking
- Topic: Keyboard hookup with minimal means (dream)
- Replies: 19
- Views: 15232
Re: Keyboard hookup with minimal means (dream)
I envision an embedded keyboard in a "Gigatron 2" platform. It would have one PCB with both the DIP chips and the keyboard switches. In that design it would be very easy for the software to sample the matrix keyboard without the addition of more chips. For example, the output bus is not us...