Equipment: eq

       Name: eq                                                      [Show more]
       Type: Subroutine
   Category: Equipment
    Summary: Subtract the price of equipment from the cash pot
    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * EQSHP calls eq
             * EQSHP calls via query_beep


 If we have enough cash, subtract the price of a specified piece of equipment
 from our cash pot and return from the subroutine. If we don't have enough
 cash, exit to the docking bay (i.e. show the Status Mode screen).


 Arguments:

   A                    The item number of the piece of equipment (0-11) as
                        shown in the table at PRXS


 Other entry points:

   query_beep           Print the recursive token given in A followed by a
                        question mark, then make a beep, pause and go to the
                        docking bay (i.e. show the Status Mode screen)


.eq

 JSR prx                \ Call prx to set (Y X) to the price of equipment item
                        \ number A

 JSR LCASH              \ Subtract (Y X) cash from the cash pot, but only if
                        \ we have enough cash

 BCS c                  \ If the C flag is set then we did have enough cash for
                        \ the transaction, so jump to c to return from the
                        \ subroutine (as c contains an RTS)

 LDA #197               \ Otherwise we don't have enough cash to buy this piece
                        \ of equipment, so set A to the value for recursive
                        \ token 37 ("CASH")

.query_beep

 JSR prq                \ Print the recursive token in A followed by a question
                        \ mark

 JMP err                \ Jump to err to beep, pause and go to the docking bay
                        \ (i.e. show the Status Mode screen)