To carry on from last week, beware of being too close to the sub. It may try to defend itself by firing torpedoes at you. If you are unlucky this may result in the destruction of your ship Otherwise, the torpedo trails can give you a valuable clue, since they emanate from the location of the sub. Another clue which you may be lucky enough to spot is the periscope. When the sub is just below the surface it may up-periscope. However, the wake caused by the periscope being out of the water is not very noticeable so you need to have sharp eyes to spot it. As well as moving about as your ship may do, it may help you to know that the submarine alternately rises to the surface and then dives to the sea bed. The sub only fires torpedoes when it is just below the surface. But it may then dive very quickly to avoid your depth charges, if its torpedoes fail to destroy your shipl Your mission is. of course, to destroy the submarine. When you think you are close enough to the sub. fire a depth charge by pressing the fire button or by pressing the spacebar. If your charge is successful you will hear the sub blowing. Otherwise you are free to fire another, if you can spare It! Note that you will have to be almost upon the submarine to be sure of getting it. Also, the deeper the sub. the less effective are your depth charges The submarine may also RAM your ship In a desperate bid to destroy you. This is, however, a rare occurence, unless you continually cruise just above the sub! To receive your briefing, press B at any time during the game. You will be given precise orders from the Admiral, plus information on which keys to use to control your ship. When the game ends you may lose or gain points, depending on the outcome. Program Notes Line No - 10-70 Remarks
- 80-250 'Once only' initialisation. Note the circumflexes in line 180 They occur elsewhere in the program as well. Use the up-arrow" key (next to CLR) on the Amstrad keyboard
- 260-310 Screen display routine
- 320-390 Every game' initialisation
- 400-790 Program core
- 400-460 Act upon various possible occurences Note that the Amstrad's AFTER interrupt facility Is used in this program to control the sonar
- 470-580 Get user's input and act upon it
- 590-790 Various calculations, mostly involving ship and sub movement
- 800-850 Briefing subroutine
- 880-910 Update display subroutine
- 920-970 Speed modifying subroutine
- 980-1030 Helm modifying subroutine
- 1040-1100 Depth charge firing subroutine
- 1110-1200 Explosion effects subroutine
- 1280-1310 'Bip' sound effect subroutine
- 1320-1340 Sets sonar flag' to on'
- 1350-1380 Clear display subroutine
- 1390-1470 Torpedo fired subroutine
- 1480-1620 End of game subroutine
- 1630-1660 Teleprint subroutine. This prints TPS like a printer would, fairly slowly with that staccato sound effect we know so well!
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