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The BBC Master 512

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GEM Version 3

The version of GEM supplied with the BBC Master 512 is number 2.0. You can download Version 3 and it will run on the 512, but there are a few things to note if you are to get it to work properly, especially if you have 5¼" floppy drives on your BBC.

Remember that, unless a program needs GEM 3, you may well be better off with the Master 512's supplied version because the effective screen is bigger (256 lines instead of 200). Also there is no colour version of GEM 3 that will run on the 512. (See my description of GEM Configuration for instructions about using the colour version.)

The package downloadable from here is actually Version 3.11. The package includes several applications in addition to the GEM system. These are: GEM Paint, GEM Draw, GEM Graph, First Word Plus, GEM Publisher, Programmers' Toolkit. There is no documentation supplied for any of these, so you will have to find that elsewhere or work out how to use the programs for yourself. Many features are self-explanatory anyway.

Installing and Running GEM 3 on the Master 512

   You can download the GEM 3 package from this site.
  You will need a mouse driver for the 512. The supplied version of GEM 2 includes a mouse driver for the Acorn mouse as part of the screen driver. This clearly cannot work with GEM 3 so you will need a separate driver.

The programs in this package were originally distributed on floppy disks. You will need to expand the zipped archives back onto floppy disks in order to use the installation routines.

You may be able to do the unzipping on a PC. However this might be awkward if you are using 5¼" disks since some of the file sets will not fit on a 360kb disk. To get round this copy the zipped archive onto a 360kb disk, take this to the Master 512 then use PKUNZIP on the 512 to expand the archive to an 800kb Acorn format disk. (In the case of GEM311_3.ZIP, even the compressed archive will not fit on a 360kb disk. To help with this I have split the files into two sets in the archives GEM311_P.ZIP and GEM311_Q.ZIP. Unzip the files in one to an 800kb disk, then add the files in the other to the same disk.)

Note that Vn 2.04g of the PKZIP package will run on the Master 512, but only if you use PCCE.


Important: You must have the correct volume label on the three GEM system disks after you have unzipped to them. (GEM Setup recognizes the disks by this.) If you are unzipping them on a PC with PKUNZIP, then use the option -$ to cause the volume label to be written. However this will not work on the Master 512. (If you try, the volume label is written as a normal file, but all other files on the disk are deleted!)

To write the volume labels on the 512 use the LABEL utility. You cannot just enter the label at the command line because there are spaces involved. But if you simply enter:


then you will be prompted for the label, and at this prompt you can enter spaces. The disks must be labelled as follows:

      Disk 1:    GEM  SYSTEM
  Disk 2:   GEM  SCREEN
  Disk 3:   GEM PRINTER

Note that there are two spaces between the words "GEM" and "SYSTEM" on Disk 1, and equally two spaces between "GEM" and "SCREEN" on Disk 2. Note also that the labels must be entered as capital letters.


The GEMSETUP program will only install from Drive A: to a hard disk, or at least to what the program thinks is a hard disk. If you have a twin-floppy-only system then you can install GEM 3 on a floppy disk. You just have to fool the program into thinking it is a hard disk. A simple way of doing this is to use the DISCID program which comes as a part of the Ramdisc Utilities package. With this program available enter:


to call the second floppy disk C:. The set-up program will then think it is a hard disk and happily install GEM to it. (It is perhaps a good idea to do this before you run GEM each time too. It can be run from floppy, but you keep getting reminders that the hard disk is not responding.)

You will not be able to get all the applications together with the GEM system on one floppy disk, but you can get several on if you dispense with the sample files.

  GEMSETUP thinks the Master 512 has three hard disks. It will install GEM so that Disks A: to E: appear on the desktop. If you want to change this then see the notes about "LASTDRIVE" in the FIDDLOAD documentation. Note that you must make this change before running GEMSETUP. Once the installation is complete then the number of hard disks cannot be changed.
  The setup program should, of course, be informed that the screen is a CGA screen running in mono. It seems best to tell it that the mouse is a "Bus mouse".
  A pointer to the GEMAPPS directory should be included in the PATH. This might be included in the GEM.BAT file. (Without it GEM will not know where the applications are, and will not be able to associate applications with file-types properly.)
  The installation disks for the GEM applications can be expanded from the zipped archives in a similar way to the system disks. The volume label does not matter for any of these, but it is important to retain the directory structure, so if you are using PKUNZIP, then remember to include the "-d" option.
  Some of the applications include an INSTALL utility. All this does in each case is to copy the files from Drive A: to Drive C:.

If it is more convenient, you can do all the installation on a PC, then copy all the files across to the 512, preserving the directory structure.

About the 512 | Software | Index