Is there a beginners guide to Hires?

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Trevor_B
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Joined: Thu Nov 05, 2020 12:31 am

Is there a beginners guide to Hires?

Post by Trevor_B »

I've been looking for something that will give me a start on how to use Hires. I've downloaded a few ".p" files but have no idea how to get them working on my Minstrel 3 (which I believe is Hires capable).

Has such a beginners guide been published anywhere - my searches tend to turn up highly technical articles which I'll possibly understand eventually but at the moment just something basic would be a start.
dr beep
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Re: Is there a beginners guide to Hires?

Post by dr beep »

Hires is simple when you know what is needed.

I got all info from the routines displayed on Wilf Rigters site.

The software is enough to get what you need.

https://k1.spdns.de/Vintage/Sinclair/80 ... Info.htm#5

What do you want to know?
dr beep
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Re: Is there a beginners guide to Hires?

Post by dr beep »

This routine will do the job.

Code: Select all

Note that HFILE must start on a 32 byte boundary (2000,2020, etc).

ORG   16516       ;(hex 4084)

START LD IX,HR    ;simple start of the hres mode
      RET

LBUF LD R,A       ;load HFILE address LSB
      0 0 0 0     ;32 NOPs = 256 pixels
      0 0 0 0 
      0 0 0 0 
      0 0 0 0 
      0 0 0 0 
      0 0 0 0 
      0 0 0 0
      0 0 0 0
      RET NZ      ;always returns

HR    
      LD B,7      ;delay
HR0   DJNZ HR0    ;delay
      DEC B       ;reset Z flag
      LD HL,HFILE 	; starts at RAMTOP or HSCRN (note below)
      LD DE,20    ;32 bytes per line
      LD B,C0     ;192 lines per hires screen
HR1   LD A,H      ;get HFILE address MSB
      LD I,A      ;load MSB into I register
      LD A,L      ;get HFILE address LSB
      CALL LBUF + 8000    ; display a line
      ADD HL,DE   ;next line
      DEC B       ;dec line counter
      JP NZ HR1   ;last line
HR2   
      CALL 292    ;return to application program
      CALL 220    ;extra register PUSH and VSYNC
      LD IX,HR    ;load the HR vector
STOP  JP 2A4      ;return to application program

HSCRN 2000        ;this is used with SRAM at 8K - 16K, 

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mrtinb
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Re: Is there a beginners guide to Hires?

Post by mrtinb »

Trevor_B wrote: Sat Feb 27, 2021 10:09 pm I've been looking for something that will give me a start on how to use Hires. I've downloaded a few ".p" files but have no idea how to get them working on my Minstrel 3 (which I believe is Hires capable).

Has such a beginners guide been published anywhere - my searches tend to turn up highly technical articles which I'll possibly understand eventually but at the moment just something basic would be a start.
It is unclear to me whether you
  • Would like instructions how to run hires software you’ve downloaded, or
  • Would like instructions how to make your own hires software.
Martin
https://zx.rtin.be
ZX81, Lambda 8300, Commodore 64, Mac G4 Cube
Trevor_B
Posts: 101
Joined: Thu Nov 05, 2020 12:31 am

Re: Is there a beginners guide to Hires?

Post by Trevor_B »

I'm a complete beginner - initially I'd like to run the software I have to see it in action, and then move on to writing some of my own.
I'd like to start by making sure I've got the machine set up correctly, making sure I can see the upper banks of RAM etc.

What I'm looking for is an initial step by step guide which explains the steps and why they have to run- something to learn from.

Trev
dr beep
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Re: Is there a beginners guide to Hires?

Post by dr beep »

Trevor_B wrote: Sun Feb 28, 2021 12:31 am I'm a complete beginner - initially I'd like to run the software I have to see it in action, and then move on to writing some of my own.
I'd like to start by making sure I've got the machine set up correctly, making sure I can see the upper banks of RAM etc.

What I'm looking for is an initial step by step guide which explains the steps and why they have to run- something to learn from.

Trev

I had the same question as Martin.
To see if settings are ok you indeed only need to run a hires game.

You can use hires in BASIC with this tool, no further knowledge needed.

https://sinclairzxworld.com/viewtopic.php?f=6&t=3124


As for selfcoding:
The easiest way is the routine above. Accept how it is working and use it.
If you want to know more then you will end up in finding out how the hardware reacts on the code.

Simple hires explanation:
Set IX to start your hires routine
Use the hiresroutine I added
Make sure your screen of 6144 bytes starts on a 32 byte counter to get a correct display. (0, 32, 64, 96, 128, 160, 192, 224)

That is how WRX, the most used method works.
dr beep
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Re: Is there a beginners guide to Hires?

Post by dr beep »

Step by step:

IX starts hires, but is called from the ROM.

Routine fills top of screen, then does 192 displays of a line
Then handles the reading of keyboard, undoes setting by the ROM and sets IX for next display.

The screen itself is altered in the program you write yourself.
dr beep
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Re: Is there a beginners guide to Hires?

Post by dr beep »

Trevor_B wrote: Sun Feb 28, 2021 12:31 am I'd like to start by making sure I've got the machine set up correctly, making sure I can see the upper banks of RAM etc.

Trev
now this is a questionable remark. How much memory do you have because there is no upper bank (in theory 16K only).
That is how the hardware knows when to do a display.
Trevor_B
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Re: Is there a beginners guide to Hires?

Post by Trevor_B »

Thanks Dr Beep - that's a good start point.

I'll have a play on an emulator first then try the real machine.

Trevor.
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