Search found 73 matches

by Bean
Wed Sep 13, 2023 12:06 am
Forum: Hardware
Topic: How to do internal RAM mod for 8-16K area ?
Replies: 6
Views: 931

Re: How to do internal RAM mod for 8-16K area ?

Thanks for all the info.
I will give it a try in the next couple days.

I am clear now on the ROMCS.
So I don't have to do anything with A15 if I only want 8K to 32K ?

Thanks again,
Bean
by Bean
Tue Sep 12, 2023 8:17 pm
Forum: Hardware
Topic: How to do internal RAM mod for 8-16K area ?
Replies: 6
Views: 931

How to do internal RAM mod for 8-16K area ?

I have the 62256 32K RAM chip and I have found schematics for 16-32K and 48-64K areas. I would like to have RAM from 8K thru 32K so that the 8-16K area doesn't get erased when resetting. (I will do the battery backed option). I believe the ROM repeats in the 8-16K area, so do I need to pull "ROM CS"...
by Bean
Wed Nov 16, 2022 3:31 pm
Forum: Development
Topic: What is important in a sprite library ?
Replies: 4
Views: 1130

Re: What is important in a sprite library ?

Thanks Greg, I'll take a look at it.

Bean
by Bean
Tue Nov 15, 2022 5:32 pm
Forum: Development
Topic: What is important in a sprite library ?
Replies: 4
Views: 1130

Re: What is important in a sprite library ?

Here is just a simple demo of how it will work.

Bean
by Bean
Tue Nov 15, 2022 1:57 am
Forum: Development
Topic: What is important in a sprite library ?
Replies: 4
Views: 1130

What is important in a sprite library ?

I am working on a sprite library for the 16K ZX81. It uses a video interrupt handler to place the sprites, when you move the sprite it puts back what was under the sprite. Right now it only handles a single 1 character sprite, but I plan to make it handle two 1 character sprites and two 3x2 sprites....
by Bean
Fri Nov 12, 2021 3:44 pm
Forum: SALES
Topic: ZXPAND for sale
Replies: 14
Views: 6752

Re: ZXPAND for sale

Not much interest here, I will be putting it on ebay.
by Bean
Mon Nov 08, 2021 3:17 am
Forum: SALES
Topic: ZXPAND for sale
Replies: 14
Views: 6752

Re: ZXPAND for sale

I am in PA USA. I'm not sure what it is worth, that's why I was asking for offers. I know they are very hard to get ahold of. None on ebay for awhile. I would prefer to sell it in the states just because of the shipping hassle. I also have a collection of other sinclair / timex sinclair stuff you mi...
by Bean
Mon Nov 08, 2021 2:22 am
Forum: SALES
Topic: ZXPAND for sale
Replies: 14
Views: 6752

ZXPAND for sale

ZXPand for sale Will ship to USA or UK only! Any questions please ask. Post your offers below. I know I could probably get more on ebay, but I want to support the members on this forum. Payment via paypal. Thanks, Bean. R.I.P. Sir Clive Sinclair. As a child my family was poor, but my parents bought ...
by Bean
Thu Aug 20, 2020 5:03 pm
Forum: SALES
Topic: 47 Sinclair / Timex-Sinclair Books for $100
Replies: 1
Views: 9979

Re: 47 Sinclair / Timex-Sinclair Books for $100

Sorry, I no longer have these books.

Bean
by Bean
Wed Aug 19, 2020 4:09 pm
Forum: Development
Topic: Pretty fast Mandelbrot set generator...
Replies: 8
Views: 10357

Re: Pretty fast Mandelbrot set generator...

I think the 0.16 format would be faster, it would just limit what area you could view. But it would let you zoom in further than my 4.12 format. So it might be worth it. I was thinking about possibly changing the existing code so that it runs in fast mode, but shows a couple frames (20 or so) after ...