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Main loop: Main game loop (Part 6 of 6)

[BBC Micro disc version, Flight]

Name: Main game loop (Part 6 of 6) [Show more] Type: Subroutine Category: Main loop Summary: Process non-flight key presses (red function keys, docked keys) Deep dive: Program flow of the main game loop
Context: See this subroutine in context in the source code Variations: See code variations for this subroutine in the different versions References: This subroutine is called as follows: * RSHIPS calls via FRCE

This is the second half of the minimal game loop, which we iterate when we are docked. This section covers the following: * Process more key presses (red function keys, docked keys etc.) It also supports joining the main loop with a key already "pressed", so we can jump into the main game loop to perform a specific action. In practice, this is used when we enter the docking bay in BAY to display Status Mode (red key f8), and when we finish buying or selling cargo in BAY2 to jump to the Inventory (red key f9).
Other entry points: FRCE The entry point for the main game loop if we want to jump straight to a specific screen, by pretending to "press" a key, in which case A contains the internal key number of the key we want to "press"
.FRCE JSR TT102 \ Call TT102 to process the key pressed in A JMP TT100 \ Otherwise jump to TT100 to restart the main loop from \ the start