Search found 692 matches
- 27 Nov 2017 21:22
- Forum: What you are doing with Lez's "Free Stuff"?
- Topic: Another build
- Replies: 27
- Views: 34292
Re: Another build
The 65C02 is a relatively new one from WDC, I think their earlier versions were -6 or -8 and may be too slow for 6mhz use - see the math at the end ! The 6847 you sent via Dave happens to be a Motorola MC6847 part, though any of the other manufacturer's versions should operate the same. The 82C55 is...
- 25 Nov 2017 17:02
- Forum: What you are doing with Lez's "Free Stuff"?
- Topic: Another build
- Replies: 27
- Views: 34292
Re: Another build
Here's what's currently on the 6502 system current build, in case someone else wants to build something similar. As the photo's in the first post show, 70% of it is built already, and I've got all the parts needed to complete it. Backplane: 7-15v DC input, on/off switch, 5 and 3.3v regulators, 4 x 6...
- 24 Nov 2017 15:04
- Forum: What you are doing with Lez's "Free Stuff"?
- Topic: Another build
- Replies: 27
- Views: 34292
Re: Another build
:o I didn't think you could push a 6847 to 6MHz.. as they're effectively multiplexed with CPU and only rated at 1MHz ?? :? On 6809 systems they are also tied to a 74LS783 Chip. The 6847 runs off it's own 3.58...mhz clock (NTSC colour burst frequency). The 6502, is one of the newer WDC W65C02S model...
- 20 Nov 2017 16:33
- Forum: What you are doing with Lez's "Free Stuff"?
- Topic: Another build
- Replies: 27
- Views: 34292
Another build
OK, it's not MTX related, or even Z80, but I've got another build running from some of the "extras" I received from Lez, via Dave. Board 1: 6502 CPU, 32k ram, 8k rom, 6mhz clock, and 74 series logic to create a memory map Board 2: 6847 VDG, 82C55 PPI, 8k ram, 74 series buffers to isolate t...
- 03 Nov 2017 14:43
- Forum: PROGRAMMING
- Topic: Generating a 60Hz Interrupt
- Replies: 3
- Views: 6953
Re: Generating a 60Hz Interrupt
I needed to do something similar for the 6502 board, I was using the BBC basic 3 rom, and the BBC used a 100hz ticker. There wasn't a way to get exactly that from the 4mhz main clock and the /256 pre-scaler setting. (/256 and 156 count =100.2 and /256 and 157 count =99.5 ) So I used /16 and a count ...
- 01 Nov 2017 21:55
- Forum: PROGRAMMING
- Topic: Generating a 60Hz Interrupt
- Replies: 3
- Views: 6953
Re: Generating a 60Hz Interrupt
I can see one issue, if you look on page 232 of the new manual, it says there's no pre-scaler when the CTC is in counter mode. However you could still use timer mode a large count value to avoid triggering too often, and then do a sub count in the interrupt handler. Possible values 4000000 / 256 = 1...
- 21 Oct 2017 12:42
- Forum: TRADING AND COLLECTING
- Topic: Free to a good home : Memotech Computing Book
- Replies: 4
- Views: 7861
Re: Free to a good home : Memotech Computing Book
Sounds like a plan.
Thank you
Thank you
- 21 Oct 2017 12:06
- Forum: BASIC
- Topic: what did they smoke when they develop MTX Basic?
- Replies: 10
- Views: 17002
Re: what did they smoke when they develop MTX Basic?
To add to the list of useful features NEXT without a variable name is allowed Shortened commands when typing ie P. for PRINT Another thing that annoys The editor putting an extra space after DATA I'd hazard a guess that the error "A" was originally "Se.A" and got cropped to save ...
- 21 Oct 2017 11:38
- Forum: TRADING AND COLLECTING
- Topic: Free to a good home : Memotech Computing Book
- Replies: 4
- Views: 7861
Re: Free to a good home : Memotech Computing Book
I'm interested!
But first a question. Is there anything in there that's likely to be "new" info ?
But first a question. Is there anything in there that's likely to be "new" info ?
- 19 Oct 2017 21:12
- Forum: BASIC
- Topic: Load a basic program without print "LOADING" etc?
- Replies: 1
- Views: 5474
Re: Load a basic program without print "LOADING" etc?
you try:
VS 7: LOAD "whatever"
And use the 1 line status screen where "Ready" usually appears.
VS 7: LOAD "whatever"
And use the 1 line status screen where "Ready" usually appears.