SWITCHING TO MANUAL

Well, Mr McCabe, welcome to the Speccy! Sorry to hear of your little problem, but I do have a couple of solutions for you.

1. You could try giving Computer Manuals a ring on 021-706 125, and they should have the manual you require.
2. I've printed your full address so that any enterprising reader out there who has finished with their manual (or has any spare lying around) can send you a copy.

MULTIFACE MYSTERIES

Why do 90% of POKEs - both Multiface and routines - NOT work with my 128k +2 (grey case)? Is it because of the memory locations being different? Is so, is there a way of calculating where an address for a 48k POKE would be on a 128k machine?
SR SMITH
Dudley, West Midlands

As you can see, I've had a couple of letters on the perilous subject of how to use the Multiface. Obviously, people are finding this piece of kit a bit of a problem. So let's go over in detail how to POKE things with your Multiface. First of all, the basics. The obvious thing to do when you've loaded up your game is to hit that big red button that stares up at you from your little black box. When that happens, a little menu comes up, chock full of options. This seems to be where most people get a little bit overwrought, choose the wrong one, and inevitably end up inflicting large amounts of pain on small pets and other innocent creatures. The way to POKE those amazing life-giving numbers into the game is to press T when the menu comes up. Then press SPACE, and type in your first number (the POKE address) and the second number (the POKE value) as one long number. Finally, press ENTER. Problem solved. Press Q to make your way back to the first menu, and Return to the game - then you're on your way to finishing the game with a minimum of effort!

When it comes to POKEs, there are usually separate ones for the 48k and 128k Spectrum. This is because most games put their routines and such in different places for the different versions of the games. A POKE for the 48k version of a game might work on the 128k version if you're lucky, but not usually the other way around. Sorry, KRW, but I don't have any such POKEs lying around, I'm afraid. I've passed on your request to Linda though - so who knows what's in store for you in the future? Also, I can't send anyone any prezzies if they don't put their full addresses on (like you, KRW). So please remember to do so in future if you write in! Si.

WELL CONNECTED

1. I've got an old Spectrum +3 disk drive which I know works. I wish to link it to the disk drive B socket at the back of my computer. What connections would I make to link it to my computer?
2. I own a Cheetah light gun. Doyou have a short machine code program for operating it from BASIC?
3. On the Expansion socket at the back of the computer there are eight data lines. If I put an 8-bit binary signal on them,
   1. How would I read the signal from BASIC?
   2. What voltage etc must the signal be?

I can't answer your first two problems, but I can help with the third. The voltages required are are 0v for a binary 0, and +5v for a binary 1. To read the signal from BASIC, you can use a simple LET a=IN xxxx, where xxxx is the port you have chosen for your data. You can't send data just by squirting it down the eight data lines on the socket, you need some additional circuitry to read the ADDRESS LINES. These lines tell you which memory address or input/output address is being used. You also need to read the IORQ (Input/Output Request) and the RDL (Read Data) signal lines as well. All these signals get mixed with each other in some 'address decoding' circuitry to produce a Chip Enable signal, which goes to a Tri-state buffer with your eight data signals. if that's not too clear, then there's a diagram down there. I can't go into the intricacies of address-decoding now, but a row of 1's has to go into the NAND gate to allow data to pass through the buffer. To do this, you take yoour port address, map it out onto the address lines, and wherever a 0 appears, put a NOT gate. Last hint is not to use any port addresses already used by the Speccy. Stick below 128 for your port addresses and you should be okay.

If you're not sure what you're doing - STOP! Consult an expert! Si.

CRACKED!

MUDDLED MODES

10 BORDER 7: PAPER 7: INK 0: CLS
20 PRINT AT 0,0; INK 7; CHR$ 163
30 IF SCREEN$ (0,0)="S" THEN LET mode=1: GOTO 50
40 LET mode=0
50 IF mode=1 THEN GOTO 100
60 IF mode=0 THEN GOTO 200
100 REM PUT 128K Routines here...
200 REM PUT 48K Routines here...


In +3 BASIC the computer prints out 'SPECTRUM'. In 48 BASIC the computer prints out 'T'. It then reads the screen and defines the mode.

My second tip is, in the June issue you showed us how to obtain the colour pink. If you print something on the screen with green paper and purple ink, it looks like the colour pink. And if you print something with red paper, purple ink and bright on, it looks like fluorescent pink.
Andrew Butler
Ashford, Kent

Thanks for that, Andrew. For your efforts expect something in a brown paper bag to be whisking its way towards you at high velocity. Si.

PURE GENIUS

This arrangement will let you use your mouse as a joystick for games. To make it work as a proper mouse, you'll need to build another lead.

I hope I've helped, Paul. If anyone has any problems with ANY hardware, they can write to me at: 71 Hamlet House, Waterhead Close, Erith, Kent, DA8 3RP. (Don't forget to enclose an sae if you want a reply).
M Lakhani
Erith, Kent

Well, I hope you've helped Paul with his problems. Truthfully though, I'm a bit dubious about your method for turning the Genius mouse into a proper SAM mouse. For one thing, you've connected a signal line to the Mouse Interrupt line, which isn't used in the mouse system... All I can say is that if you try it and it doesn't work, don't be too disappointed. Expect some goodies for that bit of investigation, Mr Lakhani. Si.

[Web page editor's note: Since writing that article, I learned a lot more about the SAM, and unless the Genius Mouse is some really really weird piece of kit, it will NOT work, no matter how you wire it up.]

SIBLING TROUBLE

Now can you do me a favour? If anyone has got any copies of YS (pre-July 1989) they are willing to swap for games (being an A-Level student I'm a money-free zone) (Likewise. Si) they can phone me on 0978 820 185 (ask for Mark).

I've plenty to choose from, from 1983 to 1992, including many full-pricers. Just the mags'll do, keep the tapes.
Mark Jones
Wrexham, Clwyd.

Oooh. You crafty sneaky person! I think that way back in the mists of time I saw something very similar in the pages of this very mag, in Program Pitstop or somewhere, but the different colours is a new one on me. Hope you get the mags you want, and while you're waiting for responses, I'll send you some stuff to keep you happy. Si.

I feel sorry for Ad if Mahoney ever catches up with him. But enough of that - if you have a problem, big or small, I'll take it on. Send 'em off to: Spec Tec Jr, Your Sinclair, Future Publishing, 30 Monmouth Street, Bath, BA1 2BW.