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TI Basic sprites with no modules   | |    Extended Basic: Fast scroll down routine
Using TI Forth - Inputs (using query, myself, emit, interpret) and Loops including nested loops (using do loop)
The Thorne-EMI games River Rescue, Submarine Commander, Computer War- released at last.
Reviews of Database 1 from SPC   ||   Spell 1 and Sort 1 from SSI
Mechatronik XB2+   | |   Genial Traveller diskazine      | |    The end of Stainless Software

  

This web page contains the text of my articles for owners of the TI-99/4a in a series called Rambles, from Issue 11 of TI*MES dated Winter (issued during the Winter of 1985 to 1986), published by Clive Scally. It is of use to users of the TI-99/4a emulators and of historic interest regarding home computer use in the UK in 1985.

Rambles from TI*MES Issue 11, Winter (issued Winter 1985-1986)


Rambles by Stephen Shaw


Hello again. Good to met so many of you at the show.

After the deafening lack of response on Forth I gave a little warning in the last issue: it worked! Many of you have written asking for MORE Forth so more there is. Thanks especially for the more detailed requests... they are most helpful.

BIRMINGHAM was fun, thanks Clive, Audrey, and everyone else. I travelled in on the first train of the day and back on the last (through) train of the day, so the timing was just right... I started the day with a very nice bacon buttie at a mere 50p from a transport caff near the Civic Hall. Did you spot the new products? I walked out with a TREASURE ISLAND module and an INFOCOM adventure.

REVIEWS FIRST...

INFOCOM ADVENTURE: PLANETFALL

available from Arcade Hardware.
I'm not a good adventure player and I haven't been too happy with the usual two-word adventures seen so far. INFOCOM however allow a more wordy input, and provide a very wordy output. If you ask for copy to be printed you can quickly go through a box of paper!

PLANETFALL is a 'standard' level adventure, ideal for adult beginners. Even I have managed 27 points (out of 80) so far. There is ample room for 'adventuring' here, and some nice touches. Ever tried picking an activated robot up? Worth trying. And if all else fails, SMILE!

The package is not cheap, but includes all the frills... well made box, colourful booklet, extraterrestrial post cards (ideal for post card collectors), personal diary, ID Card (ideal for credit card wallet...). The disk is a FLIPPY, which carries proprietary protection only. (Copy it with anything other than Disk Manager Module!). And if you should get stuck, all is not lost...

INFOCOM SUPPORT: INVISICLUE HINT Books are available in the Uk from Software Exxxess, nn Sxxxxyhurst Rd., Exxxxgton, BIRMINGHAM. tel DEI 384 SDBD for credit card order.

These hint books are VERY clever. Lots of questions are posed... some of them are of no use at all and are there just to mislead you. For each question there are one, two or three blank boxes. If there is more than one answer, they are in increasing order of helpfulness: if you only need a very subtle hint thats all you get. To read the clues you run a special felt tip pen (supplied) over the paper and the clue is revealed. There is a separate folded plan included if you need it.

A section of the book indicates how the points are accumulated, and suggests some things to try after you have scored 80 points, just for fun.

IF you like adventures, you can't live without the Infocom series. If you are not keen on adventures, take a look at a 'standard level' Infocom adventure, such as PLANETFALL (SF), ZORK I (classic underground adventure), ENCHANTER (magic), WITNESS (murder mystery) CUTTHROATS (a mercenary diver) and of course if anarchy appeals, the HITCHHIKERS GUIDE.

The ease of copying ensures that some TI owners will choose the cheap (and illegal) way to obtain these products: but will INFOCOM continue to support our machine if you do? Will the UK importer be able to support us if you do? And the packaging is worth having.


THE STICK shaftless joystick.

Many moons ago a venerable shaftless joystick appeared called LE STICK, and it is still available from MAPLIN for GBP 24.90. Both LE STICK and THE STICK are wired for Atari computers and require an adaptor for the Tl99/4A. Both use gravity sensitive mercury switches to sense the orientation of the stick.

Shaftless operation means no shaft to break. Mercury switches have the disadvantages of SLOSHING if held in a trembling hand, or if operated slightly enthusiastically. THE STICK seems less liable to slush than LE STICK. THE STICK has two very comfortable fire buttons. Use requires practice and a firm controlled grip!

Maybe a little difficult for such games as MUNCHMAN but eminently suitable for POLE POSITION or TI INVADERS. The stick insists on a sensitive touch and can make for very relaxed play (or else!).

TREASURE ISLAND is quite a rare module (try PARCO) and only just made it. It is the only one by DATA EAST to make it (the other, ANGLER DANGLER seems to have been lost in the crash). A well written game, by no means easy.

You guide a little character along mountain paths up an island/mountain which is steadily scrolling downwards. NASTIES may throw things at you or dislodge you... you can throw rocks back at them too.

CAVES transport you to exit at other caves, at random. The game insists that you pay steady and close attention at all times! and gets harder as you go along. A colour tv is not absolutely essential but recommended. As is this module. It is fun and it is different.


Some members have suggested to me that they NEVER play games and have no interest in them. I am sorry about that... I came into computing as a confirmed games player! Games of course provide a good entry point for programmers, be it in basic or machine code or whatever. They also provide recreation and relaxation.

I won't support the shoot-em-quick variety of game, although they do have their place (TI Invaders is a very good 2nd generation module). But I do question a decision to put games to one side and ignore them! Thats how I feel!

Need a GOOD DATABASE? Somehow we have not done very well with the TI99/A when it comes to a database program. PRK is a very early module, and excellent in its way, but you soon come up against the memory constraint... and PRK does NOT recognise the 32k ram!

What is needed is a disk-based data base. If they can work with a RAM CARD (such as Myarcs) so much the better.

There have been several attempts at producing a disk database for the TI. So many of them however use a fixed size record, of one disk sector, regardless of what YOU want to file! And a SSSD disk only allows 358 records, maximum.

To the rescue...
DATABASE 1 by SPC SOFTWARE. US$30 plus pp.. say an extra $5 from Box nnn, Bxxxxtwaters, NY, USA, nnn18.
This package took a few weeks to arrive, but I was very happy to receive it. MICROpendium rated it an A, and I have to agree.

The size of each record is set by YOU (and can be subsequently amended). Within that record you may have up to ten fields. Each is limited to 28 chars. The TOTAL record size say be used up between the fields with total flexibility. If you try to enter more text than there is room for, you are told and allowed to reduce the entry.

Documentation runs to 30 pages in D/V8O format on the disk. Sort and Search facilities are available, and with care, a double sort is possible. Files may be split or combined. You can with one instruction write a common string to one field of every record!

There is a disk cataloguing utility. Formatting output is easy and flexible. There is a mail facility which allows you to use selected data in letters created with TI Writer. When letters are written it is possible to amend fields (eg DATE LAST LETTER). And if the program utilities don't suit you for some purpose, records are in a very accessible format allowing you to write your own utilities.

How many records per disk? Depends on how many characters per record... if you choose 70 characters per record ( enough for many simple record keeping purposes) then you can fit over a thousand records on a single density single sided disk. If you have bigger disks you can fit more on!

A very useful general purpose database program. Mostly in ExBas for easy personalisation with the important bits in machine code! (eg sorting!).

Very highly recommended.

Spell-1 and Sort-1

In the last issue of RAMBLES I reported on a magnificent machine code game available on disk for just US$10 (plus pp) from SSI, called MICRO PINBALL. My high score on this is currently 359,300 and it remains my current favourite! However I now have a further product from SSI:
SPELL1 plus SORT1, together on one disk for US$10 plus pp (say $5). From Software Specialities Inc., P O Box nnn4, Exxxxreen, OO, USA, B0n439
The paper documentation supplied breaks all records. The piece of paper it is printed on is less than five inches by one inch. Actual documentation is in DV8O files, with about a page for each program. Adequate and sufficient.
SPELL1 is a SPELL CHECKER for TI WRITER. This machine code program reads your D/V80 files and compares each word to a dictionary. The dictionary is held in RAM and is limited therefore in size- about 2000 words possible.

The dictionary is held in a DV8O file which is read into memory first - takes a while to do. A sample dictionary is supplied but you can easily form your own, either by using TI WRITER, or let the SPELL1 program build up a custom dictionary as it scans your work.

You can of course have several dictionary files, so one for each specialist purpose is possible. Words which are in the dictionary are passed. If a word is not in the dictionary you have three choices... to add the word to the dictionary (subsequently your dictionary file is updated), to accept the word in all further occurrences in this file but not to bother saving it, or to object to it. If corrections are required, the LINE NUMBER the word is on is reported together with the word count on the line. This information can be logged if you wish.

Speed of checking depends on how adequate the dictionary is or how many errors you/TI Writer have made. Essentially it is quite fast. You do however need to make your corrections by reloading the TI Writer Editor and loading the text file. All alphabetical characters are treated as capitals... thus there is no checking for capitals in the wrong place! Anything other than A to Z is treated as a blank space. Thus RS232 is considered to be RS.

Going through a fairly large part of RAMBLES created a dictionary of 1200 words. Perhaps a little arduous to put EVERY text file through, but a useful utility.

SORT1 is a disk based sorting program. There may be lots of sorting routines around, but can they really sort ANYTHING? SORT1 will sort any file on up to 8 keys. Files may be internal or display, fixed or variable, any length.

You do not need to tell SORT1 what type of file you are sorting: it reads the disk directory itself! Your only inputs are the file names and key positions.

The sorted file is placed on disk in exactly the same format as the original file, but for sorting purposes a third FIXED file is created. The limitation on size is set by your disk system disk size and number of drives. Sorting 1200 words into order took about eight minutes: a lot faster than PRK could have managed. Two useful and powerful utilities at a very reasonable price. Well recommended.

LOGO:

As part of the User Disk Library I now have what seems to be the complete world collection of PD TI Logo material on disk: eight disks from the Young Peoples Logo Association. And very interesting they are too.
The shortcomings of LOGO in regard to memory management (and in particular file transfers) are apparent with what seems to be a lot of duplication (TI LOGO has no word such as NEW to clear procedures from memory).

Much of the material is from schools, and it is interesting to see the various attempts at drawing a heart using turtle graphics. TEST: Using Logo (or Forth) draw a heart using bit map graphics. The heart is to be drawn by a PROGRAM. Try it!

What I found very interesting was to compare these LOGO materials with the seven FORTH disks I have from the Milwaukee group... the Forth material may be a little more advanced but by and large FORTH seems to be finding the same uses by its adult owners as LOGO with its younger owners. BOTH languages are for exploration, and creation of your very own language

Orphan Chronicles

Do you like a good gossip? A good buy then would be THE ORPHAN CHRONICLES by Ron Albright, published by Millers Graphics, and available for US$l5 including post and packing, or ask Howard for a price. This reveals all about the birth and demise of YOUR computer, as well as some nasty things about the IUG.
This book is legally included in the DVD-Rom The Cyc available from CaDD Electronics and also as a zip file from TI Books.

Stainless Software

STAINLESS SOFTWARE is no more. In the THREE month period Nov 84 to Jan 85, the best selling title sold 33 copies. In the FOUR month period June-Sept l985 the best seller could manage only 4 copies. Losses for the year WOULD have bought me a double sided disk drive, a graM cracker, a 128k card and an ExBas Vn4. The money having gone, I don't have them! it was however nice to play some role in supporting the TI in the UK, and hopefully to have brought some happiness to some owners!

Stainless Software Catalogue   ||   Three disks of Stainless Software programs for TI emulator users.

IMPORTANT- disambiguation- since originally writing the above in 1985, another software publisher has been around using the name Stainless Software Ltd, since renamed. Please note the above comment has no connection at all with the second use of the name.


Super 99 Monthly

SUPER 99 MONTHLY Bytemaster Computer Services, nnn Mxxxxng Street, Szxxxur, LA, USA, 7c6bK
12 issues per year. no ads, 16 pages. All original.
AUG 85... which arrived after the Sept issue, such are the vagaries of surface mail! More on converting DF80 files to Multiplan SYLK files (May 85 issue needed). Two Multiplan spreads for Stats work. and a SUPERB article by Howie Rosenburg on FORTH programming standards. SHOULD BE ESSENTIAL READING FOR ALL FORTH PROGRAMMERS.

SUPER 99 MONTHLY was born with a loss, as a full page ad paid for in advance to appear in ENTHUSIAST 99 never appeared when the IUG busted, and of course the money was lost. The magazine Super 99 did however appear and continues.

Issues of Super 99 Monthly available to download from archive.org: Sept 84, Oct 84, Sept 85, Oct 85, Nov 85. and a run from Sept 84 to Dec 85 can be found at whtech.com


Mr M G Poskitt has written mentioning console lock outs when RESEQUENCING long programs ....
When the computer resequences, let's say it changes line 3000 to line 100... it then has to go through the program and change every reference to 3000 to 100... and keep track of where it is.
This requires a little memory. If you have a very large program there may not be enough room for the housekeeping work to be done.
result... a hung up console.

Mr E J Stocks asks about an entry in the Mini Memory Manual...
'BLWP @VMBR Equates VMBR to >6030 '
What does this mean?
Using the Line by line assembler you are limited to two letter labels and cannot use VMBR - you must use an equate.

However... if you write a program using the EDITOR/ASSEMBLER, you may use VMBR and YOU DO NOT NEED EQUATES. When the assembled code is read by mini memory it automatically does the equate to >6030.

Therefore machine code programmers can produce one source code secure in the knowledge that it will load with Ed/As AND Minimem. There is absolutely no need to produce special source code with mini mem equates if you use Editor/Assembler.

Also in the mini memory manual, we are told that the code for CIF is >23. This is wrong (page 46 refers). The XML routine code for CIF is 72. Hence DATA >7200. This quite serious error seems never to have been corrected by TI, and the source of the error is not too clear.

Extended Basic plus 32k ram scroll down routine:


By David Enterline ( is that real!) of Ohio, taken from MICROpendium, September 1985:
100 REM SCROLL DOWN
110 REM IN EXTENDED BASIC
120 REM 32K RAM REQUIRED
130 CALL INIT
140 CALL LOAD(8196,63,248)
150 CALL LOAD(16376,83,67,82
,76,68,78,48,0)
160 CALL LOAD(12288,2,224,13
1,224,4,192,2,1,37,20,2,2,2,
224,4,32,32,44)
170 CALL LOAD(12306,2,1,36,2
44,2,2,3,0,4,32,32,36,4,91)
180 FOR C=9460 TD 9492
190 CALL LOAD(C,128)
200 NEXT C
210 END

and a sample of use:
210 CALL CLEAR
220 PRINT "- THIS IS A TEST -"
230 FOR UP=1 TO 20 :: PRINT
240 NEXT UP
250 FOR DOWN=1 T0 20
260 CALL LINK("SCRLDN")
270 NEXT DOWN
280 GOTO 230

You will quickly find the limitations of this little routine, but I think you may be able to find a use for it somewhere.

TI FORTH

HOW DO YOU ENTER FROM THE KEYBOARD?
Try using QUERY... for instance:
: TEST QUERY MYSELF ;
If you run this word it will ask you to input something, then ask you again, and so on till you get tired of it. We have not inserted any means of escape so you will have to switch off.
This is better:
: TEST QUERY INTERPRET MYSELF ;
Now the computer will look at the word you type in when the cursor flashes and treat that word as a FORTH word to be executed.

Try typing in BEEP (if you have it loaded) or to fall out of the loop, ABORT.
What happens if you type in an undefined word? Try it!

Another useful word is KEY which is the equivalent of CALL KEY... but waits for a key to be pressed, then the key value appears on the stack for you to look at and perhaps use or DROP. Try:
: TEST KEY EMIT MYSELF ;
which will again form an endless loop!

A closer equivalent to CALL KEY is one which scans the keyboard and moves on, leaving a value of 0 if no key is pressed:
: TEST ?KEY IF EMIT MYSELF ELSE DROP MYSELF ENDIF ;
Lets go back to that endless loop we started with... why not test for CLEAR (Break)? Try:
: TEST KEY ?TERMINAL IF ABORT ELSE EMIT MYSELF ENDIF ;
Thats a start on using the keyboard to interact with a Forth program.

The word MYSELF used above merely repeats the word calling it, e.g. TEST
Take a look at the TEST above using ?KEY. The basic equivalent is:
10 CALL KEY(O,K,S)
20 IF S=0 THEN 10 ELSE PRINT CHRS(K) :: GOTO 10

How about those useful FOR...NEXT loops we always see in BASIC?
Well, in Forth we have one important change: you can only use two variables, called I and J.

Let's compare Basic to Forth... note that I and J are NOT interchangeable. J is only used when two loops are nested and J is always the OUTER loop counter

FOR I=I TO 20
PRINT "TI*MES"
NEXT I

is:
: TEST 21 1 DO ." TI*MES" CR LOOP ;
Note that 20 has to be 20+1=21 here!

A little more difficulty then:
FOR I=4 TO 16
PRINT I
NEXT I
becomes:
: TEST 17 4 DO I 48 + EMIT CR LOOP ;
Assuming we are in DECIMAL base!

We have to add 48 to I to obtain the ASCII of the character we wish to print. The ASCII of number 1 is 49. The I places the counter value on the stack, then we add the 48... ok?

Now let's get really tricky and use something else...
FOR I=5 TO 21 STEP 4
PRINT "STEP"
NEXT I
is:
: TEST 22 5 DO ." STEP" CR 4 +LOOP ;
We have used +LOOP here, with the STEP immediately in front of it.

Nested loops? No problem.
FOR J=1 TO 6
FOR I=4 TO 12
PRINT J+I
NEXT I
NEXT J

: TEST 7 1 DO 13 4 DO I J + . CR LOOP LOOP ;
and if you can follow THAT you are well on the way to understanding Forth control!

Oh yes .... if you really dont like using I, you can use R instead, 'cos again they are completely interchangeable ....

WHAT NUMBERS DO YOU USE WITH SYSTEM?
The answer to this is on your Forth disk, on Screen 33.
Strange but true, CLEAR SCREEN is NOT a resident operation in TI FORTH, if you fail to load -SYNONYMS (which is automatically loaded with the graphics and Editor options) then you cannot clear the screen EXCEPT by using SYSTEM!

Using 16 SYSTEM (decimal!) clears the screen, and you can see from screen 33 that the clear screen word CLS is defined in just this manner!

If -SYNONYMS is loaded there is no advantage to using 16 SYSTEM instead of CLS.

BASIC BASIC BASIC BASIC

Keep your eyes open, 'cos you will shortly come to a little surprise: 32 sprites in TI BASIC with no special modules required, no peripherals except a tape recorder...
(Ha! That even made the machine code programmers sit up eh!!!)

REVIEW: GENIAL TRAVelER

Flippy diskazine from GENIAL COMPUTERWARE
Note: The series is available to purchase as part of The Cyc DVD Rom from CaDD Electronics.
Additionally, WHT claim to have the GT available online but I can do nothing with the files they offer.

Volume One, Number One. Received by Air Mail on December 10th 1985.
Side One consists of DV80 text items, but if you do not have a TI Writer do not despair as a very clever machine code file reader is included. Both sides of the disk are accessible by menu.

On side one can be found 21 files, including introductory text, some machine code source code for programs on side two, an article by RON ALBRIGHT (that name rings a bell ....) explaining how TI ARTIST pictures can he picked up by GRAPHX... and as each has different features, the two together constitute a very powerful Graphics package. TI ARTIST also has some compatability with DRAW A BIT 1 and 2.

There is an assembly language tutorial. Articles on double column printing and sideways printing.

SIDE TWO has 29 files. Many of these are XB Program files... but they are not! Following in the footsteps of FUNLWRITER (but written independently) we have XB programs which are really machine code programs!

Contents include: Two alternative character sets for your programs, switched in instantly; a slow disk copier, a machine code disk cataloguer which can sit in memory until you need it and be called from your program or in direct mode; a DEFTABLE reader...

Also the two column program and sideways print program (the latter with two fonts supplied); microtutorials on disk sector zero and firebutton; several sector access routines and demos; the game of HOLEY MOLEY, a simple disk protector; a fascinating math demo; a maddening game of penny toss, which the computer seems to always win even if YOU toss a real coin, a program to zip through the disk and write protect all the files ( NOT a good thing to do to a machine code program format file).

Also a fast disk cleaner (eg reduces the contents to zilch but keeps the disk initialisation); and a program which allows you to save to disk OR TAPE your machine code programs in ordinary program format... so in theory an owner with just a tape recorder and 32k could load machine code. I don't seem to have any machine code programs written for XB to test this... it will NOT work with machine code programs written for Editor Assembler or for Mini Memory.

ALL of this for just US$5! Astonishing value.

The game HOLEY MOLEY is by John Behnke,

Barry Traver, the Editor, has had material published in 99er, The Smart Programmer, and Super 99, as well as being a Sysop on CompuServe.

UPDATE: In July 1988 - a full 30 months after the above review, Barry wrote to me to advise that I was the ONLY UK subscriber to his wonderful diskazine.

In 2015 youtube had a video of Barry Traver showing how to use assembly language routines in Extended Basic.

BASIC - SPRITES - NO PERIPHERALS REQUIRED


This is a little demonstration of sprites, using TI Basic with no extra peripherals and no special modules, just TI Basic and a tape recorder.

This item is taken from SYDNEY NEWS DIGEST, the publication of TI.S.H.U.G in Australia. It appeared in the March 1985 issue, and was sent in by Marcello Zannini of the Italian Users Group in Bologna, Italy.

This routine allows you to have 32 sprites in TI Basic, with NO nodules or peripherals required. The sprites do not have automatic motion, and there is no CALL COINC, but the routine opens up the 32 graphic planes, and allows a character to be placed with single pixel precision. Sprites can be moved manually to give single pixel movement of characters if required.

We have previously produced some sprites in TI Basic with the Mini Memory Module, using CALL POKEV (earlier issues of TI*MES).

Now, with no module in place, we do not have POKEV available, so the puzzle is: how, using TI BASIC, can we change memory?

TI Basic has one easy to use command which can change 8 bytes of memory very quickly... it is called CALL CHAR, and it writes these bytes into any area of VDP RAM mapped as 'character definitions'.

If you stayed awake through the article on VDP REGISTERS in TI*MES issue NINE, you will realise that by changing VDP Register FIVE, we can move the SPRITE ATTRIBUTE LIST to any part of VDP RAM, INCLUDING the area the console considers to be the character definition table.

If we can do this, then we can use CALL CHAR to write to VDP RAM in an area considered by the CPU to define characters, AND AT THE SAME TIME, define our sprites.

So, the puzzle becomes one of: How do we change the VDP registers using no modules... CALL PEEKV is not available in ordinary TI BASIC.

Now the really clever bit ( ringraziamenti Marcello!) - when you load a program from cassette, there is a HEADER at the start which tells the computer what you are loading and where to put it. Why don't we use the header to place a value into VDP RAM to change the VDP REGISTER!!

NB: If you have more than a cassette recorder, disconnect now! This article is for Console and Cassette ONLY.

The first step is to set the VDP Register, and Marcello has supplied a general purpose register changer ....
see TI*MES Issue Nine for further details.
Type in this program, then RUN it, with a blank tape in the recorder!
10 REM FILES GENERATOR
20 TO MODIFY VDP REGISTERS
30 REM COPYRIGHT IT U.G. BOLOGNA, ITALY
100 CALL CLEAR
110 INPUT "REGISTER # 0-7":R
115 INPUT "VALUE (0-255)":D `
120 A=18429-(256*R+D)
130 X$=CHR$(0)&CHR$(O)&CHRS(0)
14O OPEN #1:"CS1",OUTPUT,FIXED
150 PRINT #1:X$&X$&CHR$(INT(A/256))&CHR$(A)
160 CLOSE #1
170 END
To use the program below, with sprites, you must ENTER the values:
REGISTER=5, VALUE=15
With a value of 15, the sprite table occupies the same memory as the definitions of characters 144 to 159.
If you enter a value of 14, the sprite details are in the same location as characters 128 to 145.

After you have RUN the above program, you will have an odd file on tape.
Do a FULL RESET by typing BYE and reselect TI BASIC.
Now LOAD the tape file as though it was a program, with OLD CS1.
After you press ENTER at the end of the load, the screen will misbehave (watch for the colour black).
Now press an alphabetic key and then press ENTER.
Look .... "MEMORY FULL"!!!
Type in NEW.
The VDP register is now reset until you QUIT or BYE.

Sprites can be placed on the screen as follows:
CALL CHAR(144,"Y1X1F1C1Y2X2F2C2") (where Y1, X1 etc are values - 4 values for each sprite)
eg CALL CHAR(144,"04037A0C02057B0B") (that is 8 values for TWO sprites, TWO numbers per value)
Where each CALL CHAR carries the four parameters required for two sprites, with each parameter a two digit hexadecimal number.
Y=Row (0-191), X=Column(0-255), F=ASCII+96, C=COLOR(0-15)

What is the HEX for decimal 122?:
122/16= 7 remainder 10 (10=>A where > means HEX)
7/16= 0 remainder 7 ( 7 = >7 )
Therefore 122= >7A

As we are defining two sprites at a time, if you only want one, the final 8 values will be D0000000 to mark the end of the sprite table. If you want two sprites you need to define the next character with a D and 17 zeroes. D0 is the hexadecimal equivalent of 208.

NOTE: As with mini memory, we MUST terminate the sprite table with a value of 208. In other words the final sprite is defined with the values D0000000,

No matter which is the highest value sprite, always end the definition with a hexadecimal equivalent to decimal 208.

The following demo program builds an array H$ such that we can use this to build up the hexadecimal string required.
Ready...
1 REM IT U.G. BOLOGNA ITALY
5 CALL CLEAR
10 DIM(A$(16),H$(255)
20 FOR P=1 TO 15
30 A$(P)=SEG$("0123456789 ABCDEF",P+1,1)
35 NEXT P
40 FOR P=0 TO 15
45 K=16*P
50 FOR J=0 TO 15
55 H$(K+J)=A$(P)&A$(J)
50 NEXT J
65 NEXT P
70 REM SPRITE MAGENTA DEMO
75 F$=H$(128)&H$(64+96)
80 F$=F$&H$(14-1)&H$(208)
85 FOR Y=0 TO 191
90 CALL HCHAR(12,12,144)
95 CALL CHAR(144,H$(Y)&F$)
99 NEXT Y
(Nothing more follows in the magazine or later editions, so play around with this to your hearts content - at this time I'm not too sure what that last program was for or if it is complete!)

LATE REVIEW: MECHATRONIK EXTENDED BASIC IIplus

(See ad in this issue perhaps for availability and price?)
As press date drew ever closer, through the door comes a review copy of this new version of Extended Basic.
Not a lot of time to investigate it too thoroughly, but enough to check out the basics.

EXTENDED BASIC IIplus is a standard TI Module, and contains the standard TI Extended Basic Version 110, plus another 8k of extra CALLs, plus a pseudo-hi-res package from APESOFT (of Austria).

The documentation I had was a DRAFT running to 102 pages. These described ONLY the additions to TI XB, so you can see the changes are not trivial.

Although the documentation was thick, there were a few printing errors, a lot of literals, and in many cases the commands have not been very well explored or detailed.

WARNING: The extra chips in the module draw more power: over the TI specification, but that was sufficiently safe to permit the extra drain. The module does run hotter than TI XB! AND YOU MUST NOT OPERATE THIS MODULE WITH A CMOS 32K RAM POWERED BY THE CONSOLE. The console power supply won't take that much extra drain.

The extras available come in two types:
1. EXTRA CALLS available with the module only
2. EXTRA Graphics capability WITH 32K RAM.

Lets look at (1)Extra Calls first:
Extra calls include: BHCOPY, VPEEK, VPOKE, GPEEK, ALLSET, WAIT, MOVE, MSAVE, MLOAD, BYE, NEW, RESTORE, QUITON, QUITOFF, SPROF, SPRON, SCREENOF, SCREENON, and FIND.

BHCOPY is a screen dump program. Not very well explained, and at first I was ready to dismiss it entirely. In fact it is one of the better screen dumps! It permits you to set your printer to the best line feed spacing for your printer, and at the start of each line you can send up to ten control characters.
(with my set up I had to send a line feed, CHR$(10) )
You use it by opening a file to your printer, specifying control codes and then using CALL BHCOPY within your program.
VPEEK, VPOKE and GPEEK... similar to PEEKV and POKEV but with a GROM peek as well.
ALLSET resets lowercase as well as upper case characters.
HALT halts execution for a specified time OR until a key is pressed.
MOVE moves code within memory, and can move code between VDP and CPU ram. This allows you for instance to save screen displays in the 32k ram and change the screen INSTANTLY with a single MOVE command. There may be some capability of using the 32k as a hard disk but this is not documented.

MSAVE and MLOAD allow for CPU RAM to be saved to tape or disk and subsequently reloaded. HLOAD can load machine code programs intended for Option 5 of editor/ assembler, with the added option of defeating the auto start.
In theory we may have here the ability to save and load machine code to/from cassette, but this is not adequately documented and I have been unable to make it work.

From Howard Greenberg


New item for 1986 is a very long running story that may by now reaching its conclusion. The Thorn-EMI saga goes on. I'd just about given up with the previous management there, but there has since been a management buy-out and the new team seemed receptive to the idea of selling me the rights to manufacture the games. The deal hasn't gone through yet, but in principle it has been agreed.

Assuming all goes according to plan, I should own the games by late January. At that point it will take about six weeks to have them ready for re-sale. The intention is to have all three games on one disc selling at GBP 35.00 to anywhere in the world. For three games of this quality, that's a very fair price. The games are Submarine Commander, River Rescue and Computer War. All three are of the very highest quality and I can only say it's a tragedy that it's taken so long to get this far. Even now it may not happen - keep your fingers crossed.

[The disk of three games was on sale in Leeds in May 1986]

When I first started writing this column, I was working in the amusement business servicing Juke Boxes and Video games that were in Pubs. To put it bluntly, I hated it but the pay was good. When the company I worked for went bust, I was forced to expand the part time business of adapting arcade joysticks for the TI99/4A (thence the name Arcade Hardware) to a full time business or join Maggies Army in the dole. Gradually, I've built the business up to the point where I can make a tolerable living. Anyone whose been to NNN Hxxxon Rd will realise I haven't got rich doing this, but the point is, I love doing what I'm doing.

Working in pubs, dealing with vandalism and abuse doesn't hold a candle to dealing with pleasant, intelligent and charming people I've met and spoken to during the period Arcade Hardware has been trading. I'm constantly fascinated at the wide variety of ages and professions too. From every scale from an airline pilot to a plumber, a refuse collector to a professional computer programmer. And age holds no barriers either.

I've watched eight year olds hold their own with 69 year olds. Like most hobbies, the limitation on how deeply someone gets involved seems to be how much disposable income can be spent. But even within that, the ability to learn can compensate for a fair lack of modules/peripherals. 0f course, there have been hiccoughs and a few bad eggs, both product wise and people wise. Like the Basic Conversion Kit or the man who got very upset at discovering that having cheated me once, I wasn't going to let him do it again. But for the rest, thank you for 1985 when I'm still going and most of the home computer business is in tatters.

Thank you too for your time on the 'phone and many pleasant conversations, thank you for the letters which take time to write. Thank you also those who've shown me hospitality way beyond the normal requirements of a buyer/seller transaction. Thank you for your custom without which I'd be one of the three and a half million. .
Lets do it again in 1986.





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