Search found 59 matches

by robpearmain
Mon Dec 11, 2017 4:56 pm
Forum: Z80 Assembly
Topic: Example for setting 0x15
Replies: 2
Views: 1019

Example for setting 0x15

Where can I find sample code for setting 0x15

https://www.specnext.com/tbblue-io-port-system

Can I use the new SPECNEXT extended Z80 code?

Thanks for any help
by robpearmain
Sun Dec 10, 2017 9:48 pm
Forum: Z80 Assembly
Topic: Layer 2,Sprites, ULA in that order
Replies: 3
Views: 1394

Re: Layer 2,Sprites, ULA in that order

Fantastic. I missed the clipping functions, excellent they are in there. Essentially I want the left 75% to be the game area and the right 25% to hold the score etc (imagine trans am), with a cool scrolling layer2 and sprites that smoothly disappear off one side of the screen and reappear on the oth...
by robpearmain
Sun Dec 10, 2017 9:37 pm
Forum: Z80 Assembly
Topic: Layer 2,Sprites, ULA in that order
Replies: 3
Views: 1394

Layer 2,Sprites, ULA in that order

Is it possible to 1. Have layer2 as a scrolling background 2 Draw sprites on top of the layer2 background 3. Present the standard ULA as the last layer, effectively cropping the window sprites are displayed in E.g having the right 25% for a HUD using the standard spectrum attributes and screen memory
by robpearmain
Sun Jun 25, 2017 9:24 pm
Forum: Z80 Assembly
Topic: Books on ZX80 Assembly and/or HW Architecture
Replies: 10
Views: 2842

Re: Books on ZX80 Assembly and/or HW Architecture

I wrote the game Bipboi using the techniques referenced in David Webbs book

Found a scan of it here

https://wos.meulie.net/pub/sinclair/boo ... nguage.pdf
by robpearmain
Sun Jun 25, 2017 3:17 pm
Forum: ZX Spectrum Next
Topic: The Manual group
Replies: 17
Views: 3009

Re: The Manual group

Please count me in
by robpearmain
Sat Jun 17, 2017 8:00 am
Forum: Software
Topic: Simple Sprite editor (update to 0.4.1 10.11.17)
Replies: 16
Views: 4895

Re: Simple Sprite editor (update to 0.3.1 17.06.17)

emook wrote:
Sat Jun 17, 2017 1:47 am
updated to 0.3.1

animations, and more useful drawing features.
Thanks for all your hard work on this
by robpearmain
Sun Jun 11, 2017 5:07 pm
Forum: Z80 Assembly
Topic: Efficient way to store X coarsniate and check for right x pos
Replies: 2
Views: 686

Re: Efficient way to store X coarsniate and check for right x pos

Well it depends on how you intend to use your sprites.. For example, if you were making a single screen/flip screen type game where your sprites remain within the physical bounds of the screen, you can get away with using a byte for X and simply adding 32 before dumping to the sprite register (keep...
by robpearmain
Sun Jun 11, 2017 7:18 am
Forum: ZX Spectrum Next
Topic: Sprite cliping?
Replies: 10
Views: 1976

Re: Sprite cliping?

by robpearmain
Sat Jun 10, 2017 10:01 pm
Forum: Z80 Assembly
Topic: Efficient way to store X coarsniate and check for right x pos
Replies: 2
Views: 686

Efficient way to store X coarsniate and check for right x pos

The sprite documentation shows, due to possibility of writing over the border to allow an x coordinate 0-319 where the X MSB is written out when showing the sprite

What is the most efficient way of storing the x pos (9 bytes) and checking if hit 319 and if so set to 0
by robpearmain
Sat Jun 10, 2017 5:35 pm
Forum: Z80 Assembly
Topic: Can we get source code to TESTSPR2?
Replies: 39
Views: 6783

Re: Can we get source code to TESTSPR2?

You need to make sure to set the sprite register number EVERY time before changing the co-ords, otherwise what happens is you set the registers for each successive sprite -- creating the funny trailing pattern, at least under emulation - I don't have real hardware to test, but it appears that upon ...