8-Bit Software Online Conversion

                             From: K3H (ALBERT SCHOFIELD.) Subject: TAPE TO DISC ON THE BBC 'B' Some cassette based games can only be made to work on disc by loading part of the game via Sideways Ram. COMBAT LYNX is one such game. This game is in three parts, COMBAT, LYNX and LYNX1. Part one is a basic program and *RUNs the second part. The second part is the loader for the third part. It is locked but works just as well when unlocked. The third part is also locked but will not work when unlocked. It is also a very long file (&7C00). The load address is &400. It therefore needs downloading but because of its length, I have found this impossible to do. Therefore it has to be loaded from Sideways Ram and locked in the Rom Filing system. COMBAT LYNX can of course be transferred to disc using SNAPSHOT. But this causes corruption at the bottom of the screen and also the flashing cursor is present. So for a perfect load SWR loading must be used for the last part. So load in the first part. Delete line 20 and add the following lines:- 20 *KEY10 CLS|M*LOAD LYNX|M*ROM|M *OPT1,2|MCALL&2C00|M 30 ?&FF30=0:*LOAD LYNX3R 8000 40 ?&FF31=0:*LOAD LYNX2R 8000 50 ?&FF32=0:*LOAD LYNX1R 8000 60 CALL!-4 Save this to disc as COMBAT. This file works with the Watford Rom/Ram board. Otherwise you may have to alter lines 30, 40 and 50 to suit your SWR. Load the second part from cassette with an unlocking utility using *LOAD""2C00 and save it to disc using *SAVE LYNX 2C00+2C00. The third part, due to its long length, will have to be transferred to disc using the one block at a time. The method which I described in an earlier article. Also because the file is locked, the file that does the transferring will have to be combined with an unlocking utility. The file can now be saved into three ROM images and also locked. To do this I use the excellent ROM Image Generator by Mark Lock from the november 1987 issue of BEEBUG magazine. This allows you to lock the files and also continue from one rom image to another with long files. Save the rom images as LYNX1R, LYNX2R and LYNX3R and it is essential that the long file itself is saved as LYNX1. It is also essential that the rom images are loaded in the correct sequence. The first file (COMBAT) does this. Chaining COMBAT will now load the rom images and *RUN the game. LYNX1 will now load from the RFS in about twenty seconds and give a perfect display.  From: 15A (Steven Flintham) Subject: Custom Master MOS's I was interested to see Jeremy Stanton's message about this in the last issue as I'd been thinking about something along these lines myself. Given a socketed MOS and an EPROM blower capable of blowing a sufficiently large EPROM (assuming they exist) it should be possible but I don't actually know. I've assumed it's possible for the rest of this message. Replacing a complete ROM with another one would probably be relatively easy although I think replacing the Terminal and View ROMs would be difficult. The Master Reference Manual Part One, page F.2-2 refers to ROM 15 as the MOS, 'incorporating... the Terminal emulation software' and (although I can't find a more definitive reference) I seem to remember an old Micro User claiming that the MOS's flood fill code is located somewhere in the View ROM. Anything more involved might be difficult, especially modifications to the MOS itself, but I suppose someone with sufficient talent and patience could do it. One possibility might be to modify the MOS so that the RTC supports dates in the next century correctly. I don't really know but I suspect that if it was acceptable to no longer support years in this century it would be possible to just patch the code rather than rewrite it. This is probably not feasible or worth the effort, since the date isn't used very much by either the MOS or any other software.  From D6G Sprow 1Mbit ROM ========= Carving the waste out of the Master's MOS was the subject of J Stanton's letter last issue.I did think of doing this some time back as I have some blank 1Mbit (128Kbyte) roms and a suitable programmer. The reason why I didn't was for the following reason: The BBC OS1.20 is 16k and,compared with the Master is very simplisitic,it has none of the advanced graphics (eg. L/R/U/D window scrolling no ellipse fills no parallelograms etc...) nor all of the text for *STATUS and the extar text for the new *HELP MOS nor all of the new commands.I don't think even Acorn could squash all these new features into just 16k. So how did they manage? - given that 16k MOS core 16k VIEW 16k DFS 16k ADFS 16k EDIT 16k BASIC 16k TERMINAL 16k SHEET ==== 128k (1Mbit) To get around this space problem Acorn put all the infrequently used stuff in the other ROMs.For example TERMINAL is fairly simple and doesn't occupy the full 16k,so the spare space is used to hold the default character set (to prove this CHAIN my simple program on this disk: SCRNROM which dumps to screen the TERMINAL image.You'll see the character set at the end. Similarly,the *SRLOAD/SAVE commands appear at the very end of the DFS rom. Hence,removing one rom would cause the MOS to fail.Obvious exceptions to this are (for example) BASIC IV which we know takes the entire 16k.It would be 'safe' to remove this,perhaps VIEW too. Contact me at the usual address (see separate note) 8BS mail me on D6G Robert Sprowson.  From D6G Sprow Mike Mallet (D6K) wanted to know if there was a relevant link in the Master to make it colour composite video. No such luck.The relevant bit of info is as follows,and can be found along with over 200 other hints on BBC147 from the PD library.Send Chris 50p and a disk with stamp. The reason why Acorn didn't make all composite video colour is because they expected most people to use the RGB with a Cub monitor.Making the colour modification degrades the RGB output - looks like you can't have the best of both worlds! The article reads: 170. Composite video colour for Master ÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷ To get a colour signal from the CV output socket, I hear that you can solder a 470pF ceramic capacitor between the emitter (right leg) of transistor Q12 and the base (centre leg) of Q13. These are located between the CV and RGB sockets, and although it is a slightly delicate soldering job, it is nowhere near as tricky as the equivalent modification on an early BBC B. Contact me at the usual address (see separate note) 8BS mail me on D6G Robert Sprowson.  From: D8J (John Robson) Subject: Sticky Keys (again) I have had the same trouble with keys on the keyboard sticking or not working from the Electron to the BBC Master 128. Like other users I also use WD 40 but with a slight difference:- squirt a little WD 40 around the top of the key spindle (take the key pad off first), work this well into the actual key by pressing it up and down and from side to side. After this it has two choices - it works or it not works! Get some surgical spirit and a child's school paint brush, dip it in and brush it around the top of the spindle so it runs to the inside of the switch. This thins the WD 40 down a little. In the morning turn the machine up- side down, key pad still off, and let the fluid run out by pressing the key about once every hour a few times throughout the day. After about 6 hours switch on and it should be working again 100%. If not then it will have to be unsoldered using a 25 watt soldering iron and a solder sucker, and a new switch put in. This is not hard to do, if you have a spare machine for spares. --------------------                    