Apricot GEM/1

One of the earliest releases of GEM was on the Apricot F-Series; the review in Personal Computer World compared prereleases of the F-Series version and the PC version. These screenshots are of GEM 1.2 on the FP (17 July 1985) and the F1 (9 September 1985).

These screenshots have had their height doubled to compensate for the Apricot's 640x200 screen resolution.

The desktop looks pretty similar to GEM/1 on the PC. However, it shows in black and white even though the F1 is capable of colour; at this resolution, the F1 has only four colours (by default black, white, red and green) and the desktop is drawn in the fifth (black on systems with 4 colours or fewer; blue otherwise).

GEM for the FP includes three drivers: a monochrome one for the internal screen, a 4-colour one for computers with 64k video RAM, and an 8-colour one for computers with the full 128k video RAM. With the monochrome LCD driver, GEM looks something like this.

GEM on the FP, using the 8-colour driver. There are now enough colours to make the desktop blue.

On Apricot PCs, drive letters are allocated to hard drives first, floppies second. Hence on this (emulated) FP, A: and B: are hard drives, C: and D: are floppies.

The PCDOS version of GEM/1 has a "Format disk..." on the 'File' menu; this runs the DOS FORMAT command on the selected drive. On the Apricot, this reads "Utilities..." and selecting it produces the message box shown above.

The wording in the FP version is a little different, but the sense is the same.

The utilities mentioned in the message are those shown in the file window on the first screen. This is the F1 version of CONFIG.APP, displaying serial port settings. For some reason both CONFIG.APP and GEMDISK.APP open a main window, despite the fact that it's never used for anything (all the functions bring up forms to enter data, like this serial port configuration screen).

Another screen from CONFIG.APP, this time from the screen setup.

On the FP, CONFIG.APP eschews a menu bar in favour of a modal form containing five clickable bitmaps; these then bring up the same panels seen in the F1 version. Settings changes made in CONFIG.APP are optionally saved to the first sector of the boot disk when the application is closed.

This is GEMDISK.APP on the F1; here we see GEM proving that it is indeed running on a colour system. GEMDISK contains three functions - a formatter, a utility to copy whole discs, and and a utility to copy files from one disc to another with only one drive (this is a wrapper for SCOPY.EXE, also visible in the first screenshot).

Apricot GEM contains an extra Desk Accessory - "Std/Alt Palette". The colours in the alternate palette are blue, yellow, red and black. The screenshots in Personal Computer World use this palette.

On the FP, the alternate palette has 8 colours and is accordingly even more garish. The option used for this is also used by the monochrome / colour setting in Activity, another graphical front end supplied with some Apricot computers. If GEM uses the standard palette, Activity is in black and white; if GEM uses the alternative palette, Activity displays in colour.

The FP also has another accessory to enable or disable voice input.

This is one of the screenshots from the Personal Computer World review. As you can see, it's very similar to the released version 1.2, but there are a few differences:

• The screen appears to be bigger — say 640x256 rather than 640x200. While the F-series video hardware does support a 640x256 mode (selected by setting the monitor to 50Hz in CONFIG.APP) the supplied GEM drivers always run at 640x200. Possibly a separate set of drivers was required for these modes.
• The "close" button is an open square, rather than a big solid rectangle.
• The drive icons are on the left (as in Atari GEM) rather than on the right.
• The font used appears to have serifs.
• To delete files, you drag them to the "waste bin" rather than "trash"; and the icon of the bin is flat rather than pseudo-3D.
• GEM applications are .EXE files, not .APP files (the Output program is called OUTPUT.EXE, for example). Their icons aren't the ones that were finally used either.
• There are minor wording changes, such as a count of "files" rather than of "items".

As part of my experiments with writing GEM video drivers, I created a program to exercise different code paths and trigger possible bugs. When I tried it on the F-series drivers, I discovered that all F-series drivers have at least one bug in vro_cpyfm(), which you can see on the above screenshot. The screen ought to look more like this:

There's another one that only shows up in monochrome and 4-colour drivers: text drawn in transparent mode that's aligned on an 8-bit horizontal boundary is drawn with a white background.

(Bugfixed versions of these drivers are available for GEM/1 and for FreeGEM. The bugfixed versions also include support for the 640x256 video mode).

Internally, the F-series GEM drivers are mildly interesting to those interested in such things. Firstly, they still contain strings reading 'APRICOT GSX 2.0 BETA RELEASE', harking back to the days when the GEM VDI was called GSX 2.0. Secondly, to improve performance (the Apricots being quite slow computers) various operations attempt to speed things up by generating code on the fly and then executing it.

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John Elliott 1 March 2012