Universal Basic Library

UBL is a simple Universal portable Basic library for a range of machines.

You can download it from here:
https://github.com/orac81/miniapples/raw/refs … /ubl-latest.zip

(Dungeon Maze, one of the examples.)

It currently has support (to varying degrees) for Commodore 8bits (C64, C16, VIC20, PET), DOS QBasic/BasicA, Apple2, Dragon32, BBC, ZX-Spectrum, Amstrad CPC, MSX, TRS80, Exidy Sorcerer and Ohio Superboard.

See the file UBL25.TXT for the actual source code for each target.

You can perform a range of simple tasks, poke/peek the vdu, set colour, etc, by using gosub calls in your code. By merging the UBL library for your target system, the same program should run on many machines. I have tended to concentrate on the Basics that are either Microsoft Basic derived, or later ones that have a fair degree of compatiblity.

But expect for there to be bugs and omissions, I have not cross tested every combination at this stage.

The Library is written mostly in Basic, and is in Lines 1-49, and 9500-9999. Why those lines? Some time critical functions, ie; peek/poke screen, are fastest when located at the program start. But other lengthier routines can be placed high, too much code low-down will slow up the main program.

I have tried to make UBL "Compiler friendly", so that code should compile fairly well, given the limits of the Basic language.

You code should be at lines 100-9499, and one of the first calls should be gosub 9500, which initialises UBL code. UBL uses variables starting with the letter U, care should be taken not
to reuse them in your code.

UBL is mostly based around standard Upper case ASCII, so that the calls to poke/peek use ASCII codes. There is a provision for "extra characters", so far a few PETSCII chars, the cards (Heart/Diamond/etc) Ball (81), Grey (102), and some form-line chars. On non-cbm these map to nearest ASCII equivalents.

While I have made a few disk images, I have supplied the code as simple text files to cut/paste into a users preferred emulator. In the main UBLXX.TXT file you will find a number of different libraries for each platform. Just copy and paste the one for your desired system.

There are so many different systems, and different methods for transfering and implementing programs on real hardware, I feel this method is the best. Propogating small code changes across many different formats is difficult, particularly at this early stage.

I have supplied a Commodore D64 image file "ubl-cbm.d64", with sample programs to load and run. The Commodore lib will autodetect the machine and set up variables accordingly. Note that you should use LOAD "PROG",8 and not: LOAD "PROG",8,1 since I have saved the programs at $0401 so that PET computers can load them.
The programs will readily compile under Blitz, Austrospeed, Basic64 etc, which definitely makes the games more playable.

(Ceeblox game, c64.)

API Command Summary

(Use "gosub linenumber" to call. Note that the var U is a common parameter.)

(To calculate a VDU pos for these functions, use "u=x+y*ux")

3 Poke VDU pos U with char U1, Colour U2
ie: u=4*ux:u1=65:u2=2:gosub 3:rem put 'A' at VDU(0,5),color 2.

4 Poke VDU pos U with char U1, (no colour set)
ie: for u=0 to ux-1:u1=u+32:gosub 4:next:rem show chrset

6 Doke VDU pos U with char U1,U2.
8 U1 = VDUPEEK (U)
9500 Initialise UBL. Return VDU size UX,UY, use these in your code.
9560 Return getkey() in U (ret zero if none)
9570 Return getkey() in U (wait for key)
9580 Return special (PETSCII) code, poke-char(u),printable(u1)
(otherwise typical asc "%*OHDSC#_^)(+-!")

9590 Convert Asc U to peek/poke code
9600 u=random number 0..1
9610 Output a string (u$) to vdu pos (ui,uj)
9630 Convert cga-type rgbi (0-15 bits:irgb) in U to local color poke val U.
9650 Set print cursor pos(ui,uj) (1..n)
9670 Clear the VDU.
9680 Set screen colour (u)
9690 Fast fill (u3..u4 step u5) with u1, (colour u2 if set)
9700 u2=colorPeek(u)
9710 Return time in secs (uf=float var)

In the "example" folder is a collection of simple samples, demos and games. Paste that program into your emulator, then copy/paste the section of the library for the machine you want to target from the source library, ie: UBL25L.TXT

These examples should be viewed as part of the documentation. Most have elementry instructions on the title screen, but for the odd one that doesnt (maze, ugomoku) use keys about letter "S" to move, enter to make move, "k" to exit. I left out the title screen to save memory on these ones.

The examples are also in the "qbasic" folder, ready to run under QBASIC. But note, some of the programs will run too fast, some allow a "speed" setting on their title screen. Capslock might be needed for some examples.

I have tended to write the code in lower case, since the emulator I use the most (Commodore WinVice) accepts paste in lower case. If you need upper case, use a utility that converts a text file to upper case.

Finally I will say again, this library is very simple, and at an early stage, with bugs and ommissions. Please treat it as such!

(Ugomoku on the Vic20.)

UBL is free software, under the GPL3 licence.