WARNING - Disconnect your equipment from the mains supply before removing the cover or any screws. In the case of computer monitors or CRT displays make sure you discharge the tube before commencing any maintenance. The information provided on these pages is for your information only - any electrical works should be carried out by a competent person. Retro-Zone.Org or any of the writers cannot be held responsible for any injury or damage caused by the use of this information.

DISCLAIMER - Retro-Zone.Org or any of the writers cannot be held responsible for any damage caused to your equipment. Use this information at your own risk - only if you feel competent to do so. Every Project here was undertaken with all possible safety precautions in place - please ensure you do the same. Before you begin any works on sensitive electronic equipment make sure you have "earthed" yourself to prevent any static charge damaging the circuits of your equipment.

 

ACORN BBC MICRO Model B INSTALL SOFTWARE ROM   Step 1: Before you start please read the small text printed above.   Please note that this guide is for installing additional ROM chips into your BBC Micro Model B. The photo to the right shows a BBC Micro Model B computer.
	Step 2:   First lets remove the top cover of the computer. Unscrew (and store in a safe place) the two screws to the rear of the computer unit (shown right marked in red.)
Step 3:   Next turn the computer upside down and unscrew the 2 screws marked in red (as shown in the photo to the left.)
	Step 4:   Now you can lift away the top cover of the computer to expose the circuitry inside..
Step 5:   Unfortunately the part of the circuit board we are after is underneath the keyboard. So the next step is to remove the keyboard.   Take note of the small nuts (marked in red) in the photo to the right. You will have to hold these still while turning the keyboard securing screws indicated in the next step.
	Step 6:   While stopping the small nuts in step 5 from spinning - unscrew the 2 fixings marked in red indicated in the photo to the left.
Step 7:   Carefully dislodge the keyboard from it's position - and lift from its bottom edge and lift upwards. Rest the keyboard upside down for the moment.   Now we can see our ROM sockets (marked in blue.)   Please Note: Only the 2 sockets to the right are suitable for software ROMs. The left most socket seems to be reserved for operating system extensions such as disk commands or peripheral controls.
	Step 8:   Locate your ROM chips!   Take note of the "notch" on one side of the chips - this notch corresponds to a notch on the sockets inside the computer.
Step 9:   Take note of the notch on one side of each of the ROM sockets. The ROM chip must be inserted so that the notch of the chip and the notch of the socket and on the same side (one over the other.)   We are going to install our ROM chip into the central free socket. Do not install into the left most socket as this is not compatible with application ROMS.
	Step 10: Insert the ROM chip into the central free socket- ensuring the notches are aligned correctly (as shown in the diagram) and that all the pins are over the top of holes. Push down firmly but evenly to push the chip into position.
Step 11:   Step back and admire your handy work! After replacing the keyboard and top cover - power up your BBC micro.
	Step 12:   Success - the ROM chips loads on start-up and the application runs!