8-Bit Software Online Conversion

            This article has been prompted by a number of people asking about ROMs and how to fit them. Please do not hold me responsible for any damage you may do to yourself or your computer after reading this article! If you are unsure about anything, either DON'T do it, ask someone who knows or give 8BS a ring (0482 896868) for more info.       By C.J.Richardson. There are several different versions of the BBC. Each has different slots for ROMs. Some have ROM boards fitted. This article will not attempt explaining how to fit ROMs onto these boards.         You may need to rearrange the order of the ROMs in your machine. ROMs may be removed by placing a screwdriver under the end and gently twisting. Move from one end to the other, easing the ROM out a little at a time. Be careful not to touch or bend the legs. There are two types of ROM that may be fitted into your computer. They are: 1. Language (BASIC, WORDWISE etc) 2. Service (DFS, PRINTMASTER etc) When the computer is switched on, it looks to see what order the ROMs are placed into the ROM slots. It starts at the highest and moves down to the lowest. The ROM in the highest slot gets priority over ROMs in lower slots. The language entered when the computer is switched on will be the language in the highest socket. So if for instance you insert a WORDWISE ROM into a socket higher than a BASIC ROM, then it will be WORDWISE that you enter when the computer is switched on. If you have fitted service ROMs with the same * commands, then the ROM in the highest socket will take priority.   A link is a switch which tells the computer how a slot is configured. For more details, see each relevant section. A link comprises 3 small metal prongs and a small piece of plastic with a metal sleeve. The plasic will push over 2 of the prongs. Which 2 prongs it is fitted over tells the computer how the ROM slot is configured. If the 3 prongs run from left to right, if the sleeve is fitted over the first 2 prongs, then the link is set WEST. If the sleeve is fitted over the last 2 prongs then the link is set EAST. The same convention follows for links that run from top to bottom (NORTH and SOUTH).       Each ROM has a notch at one end. If you insert the ROM into a ROM socket the wrong way around you are liable to damage the ROM. A good guide is to look at the other ROMs in the computer and insert the ROM with the notch in the same direction as the other ROMs.       Remove the cover. Remove the keyboard. The sockets are to the bottom right. There are five sockets. The left hand one contains the Operating system and is the highest socket. Normally BASIC is fitted to the right of this. The other three may or may not already have ROMs fitted. You may interchange the ROMs, but leave the far left hand one (the operating system) where it is.       Remove the cover. The 6 sockets are to the top left of the board. The top right ROM of these 6 is the Operating system AND BASIC (the ROMS on a BBC+ are 32K) this is the highest socket. To the top left of the board there are 5 links. These links are each associated with one of the other 5 slots. Link Associated with Top 18 Top row, 2nd slot from left 15 Top row, left hand slot 12 Lower row, far right 11 Lower row, middle Bottom 9 Lower row, left hand slot The slot with the highest priority is the slot at the top of the above list. Set the links EAST for a 32 K ROM and WEST for a 16 or 8 K ROM.         Remove the cover. The ROM slots are at the right hand side. The slot with the highest priority containing the operating system, BASIC, ADFS and DFS is at the top of the row of 4 slots. The configuration links are links 18 and 19. These are situated to the left of the slots. Link 18 is in line with the lowest ROM slot. Link 19 is in line with the slot below the BASIC ROM. The link number is written on the circuit board as "LK19" or "LK18". For the top socket to recognise a ROM inserted into it, you must switch link 19 EAST. For the lower socket to recognise a ROM inserted into it, link 18 must be EAST. There are also 2 cartridge slots on the Master. This enables you to put ROMs into the cartridge and then push the cartridge into place without having to take your computer to bits.           Remove the cover. The sockets are situated at the right hand side and run from bottom to top in order of priority. The Operating system, BASIC and ADFS are fitted into the bottom socket. Link 11 is situated to the right of the top socket. If this link is set SOUTH then the computer will recognise a ROM fitted in the slot just above the BASIC ROM. If link 11 is set NORTH then the computer will recognise hardware fitted to the expansion connector on the right hand side of the casing.    