Time-Gate

Quicksilva

Products: Time-Gate

Developer(s): J. Hollis

Date: 1984

Type: Program

Platform(s): TS 2068

Tags: Game

A space shoot-’em-up. You fly the time ship Void-Runner 1 for the Temporal Brotherhood against the Squarm, an insect-reptile race that has taken over the galaxy. The long-range scanner shows 18 sectors with planets and alien craft; you pick a sector with L and jump with J, then line up the target computer with the joystick or keys 6–9 and fire lasers with 0 against a 3D moving star background. Once a sector is clear, the time-gate can be found and you travel back to an earlier date. Damage to the shields, weapons, target computer, scanner, engines and jump drive is shown by colour, and you can land on a planet with P to repair and refuel, which uses up the planet. There are five skill levels.

The game reads “PROG:TIME-GATE BY:JOHN HOLLIS”, “QUICKSILVA 1982”, and the training manual “BY JOHN HOLLIS … © QUICKSILVA 1982”. The TS2068 loading screen program QS LOGO has the REM lines “created 25TH NOVEMBER 1983” and “author S. S. DOSANJ (BITTERNE SOFTWARE)”.

What’s in the download

Side A: QS LOGO (a loading screen), then MANUAL, a BASIC training manual, with panel, 3,000 bytes of code holding the picture of the ship’s control panel.
Side B: QS LOGO again, then the game, TIMEGATE, 28,140 bytes loaded at 28000 and started at 56000.

Program Analysis

Training manual

MANUAL draws the TIME-GATE title letter by letter with PLOT and DRAW, with a beep and a border flash for each, then pages through the story and explains the four instrument sections: the long-range scanner, the message system, the target computer with its four indicators (vertical and horizontal tracking, approach speed and distance) and the status squares, which go from green through magenta and red to blue as a system is damaged. It ends with the game controls, offers to repeat the instructions, and then loads the next program from tape.

Notable Techniques

Lines 70–72 POKE two 12-byte LDIR routines at 49000 and 49012. One copies 2,048 bytes from the panel code into the bottom third of the display file, the other copies 256 bytes of colours into the matching attribute rows, so the control-panel picture appears at once (line 80).
Subroutines 81–89 blank parts of the panel by POKEing attribute rows to zero, so each instrument section can be shown on its own as it is described.

Potential Issues

Lines 2330–2350 read INKEY$ three separate times, so a key press can be missed; only lower-case y and n are accepted.
The manual says to choose a skill level with keys 1 to 4, but the game has five levels (LEVEL ONE to LEVEL FIVE).