The write_pod (I/O processor) subroutine - Elite on the BBC Micro and NES

       Name: write_pod                                               [Show more]
       Type: Subroutine
   Category: Dashboard
    Summary: Implement the write_pod command (show the correct palette for the
             dashboard and hyperspace tunnel)
    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * tube_table calls write_pod


 This routine is run when the parasite sends a write_pod command. It sets the
 I/O processor's ESCP and HFX flags to ensure that the correct palette is
 shown for the dashboard and hyperspace tunnel (ESCP affects the dashboard and
 HFX affects the hyperspace tunnel).


.write_pod

 JSR tube_get           \ Get the parameters from the parasite for the command:
 STA ESCP               \
 JSR tube_get           \   write_pod(escp, hfx)
 STA HFX                \
                        \ and store them as follows:
                        \
                        \   * ESCP = the new value of ESCP
                        \
                        \   * HFX = the new value of HFX

 RTS                    \ Return from the subroutine

[X]

Configuration variable ESCP = &0386

The flag that determines whether we have an escape pod fitted, matching the address in the main game code

[X]

Configuration variable HFX = &0348

A flag that toggles the hyperspace colour effect, matching the address in the main game code

[X]

Subroutine tube_get (category: Tube)

As the I/O processor, fetch a byte that's been sent over the Tube from the parasite

Dashboard: write_pod

[Elite-A, I/O processor]