Search found 50 matches

by David G
Wed Jan 27, 2021 3:01 am
Forum: Development
Topic: how best to fit an RPG into 1k?
Replies: 2
Views: 67

Re: how best to fit an RPG into 1k?

Crayon21 wrote: Tue Jan 26, 2021 6:35 ama routine for allowing movement on screen (i am hoping to allow for wasd or arrow keys).

your character is just a dot...
For sample code for a standard ZX81 see, ZX81 Machine Code demo: how to move a dot around
by David G
Wed Jan 27, 2021 2:33 am
Forum: Development
Topic: ZX81 Machine Code demo: how to move a dot around
Replies: 0
Views: 20

ZX81 Machine Code demo: how to move a dot around

a sample program that shows how to move a dot around the screen using the arrow keys MOVEDOT_4K.p Attached is the Assembly file for ZX-IDE MOVEDOT_4K.ASM (get ZX-IDE for Windows at https://www.sinclairzxworld.com/viewtopic.php?f=6&t=1064 -- download FASMW-ZX) REQUIRES 4K OR MORE MEMORY AS IT USES A ...
by David G
Mon Jan 25, 2021 11:29 am
Forum: Welcome Area
Topic: Hello from mid-Pacific
Replies: 5
Views: 503

Re: Hello from mid-Pacific

Thanks for the kind words. Here is a piccy of my ZX81 along with the papers that came with it: * ZX81 Assembly Instructions * ZX81 Basic Programming manual * SYNC magazine special issue * Syntax ZX80 newsletter April 1982 Vol 3 No 4. I think this may have been sent to me later on but it was because ...
by David G
Thu Jan 21, 2021 10:51 am
Forum: Welcome Area
Topic: Hello from mid-Pacific
Replies: 5
Views: 503

Hello from mid-Pacific

Aloha! Greetings from Hawaii. I'm back after a few years away, 2020 has given me time to try programming again My first computer was a ZX81 in 1982 -- as soon as the price came down to $99 US dollars I ordered one and put it together on the kitchen counter. It was the first project I ever soldered a...
by David G
Thu Jan 21, 2021 9:28 am
Forum: Hardware
Topic: ZX81 ROMs 3 types?
Replies: 40
Views: 1823

Re: ZX81 ROMs 3 types. Confirmed!

Good information. I've been working on machine code which runs on either of the different ROMs. This inspired me to update my test program runs in 1k. These are some typical ROM routines a machine language program might call (FAST, SLOW, PRINT-FP, etc). It will crash if we call any of these higher a...
by David G
Thu Jan 21, 2021 9:28 am
Forum: Hardware
Topic: ZX81 ROMs 3 types?
Replies: 40
Views: 1823

Re: ZX81 ROMs 3 types. Confirmed!

I did not know about the third ROM, thanks for the information
by David G
Thu Oct 09, 2014 6:59 am
Forum: GAMES
Topic: 1k machine code game "Viper Jr"
Replies: 1
Views: 1323

1k machine code game "Viper Jr"

Found an old folder with the hand-written listing for an old machine code game. Originally, in 1982 it was a proof of concept, so it's quite simple, but also a bit of fun. It was written for the 4k, but I just realized it will run on 1k too. viper1k.JPG P file is available for download. The BASIC/as...
by David G
Mon Oct 06, 2014 12:44 am
Forum: Sinclair Misc
Topic: BASIC
Replies: 29
Views: 10917

Re: BASIC

Here is a one-file program for ZX-IDE . contains BASIC and assembly (machine code) in one file. ZX-IDE will create a program and run it in EightyOne emulator by pressing one key F8. Just copy into same folder as ZX-IDE. The machine code take a number as input, column number of screen row 1, and inve...
by David G
Sun Sep 28, 2014 5:16 am
Forum: Development
Topic: ZX-IDE and ROMs
Replies: 5
Views: 1690

Re: ZX-IDE and ROMs

Hi, welcome to the club. DB is "define byte", so the example aboves define two bytes. Result is two bytes long. Some assemblers (but not all) also do other functions with the ORG statement. But here it only defines the origin address of the code that follows. One helpful feature of ZX-IDE is to pres...
by David G
Tue Sep 23, 2014 9:27 am
Forum: Lambda 8300/ Power 3000 Lounge
Topic: Reviving Lambda / Power 3000 tape
Replies: 4
Views: 5962

Re: Reviving Lambda / Power 3000 tape

Reportedly the tape format is almost the same as a ZX81. See http://sinclairzxworld.com/viewtopic.ph ... bda#p14001