Screen buffer: screenBufferLo

       Name: screenBufferLo                                          [Show more]
       Type: Variable
   Category: Screen buffer
    Summary: The value to add to scrollScreenLo for each direction to get the
             low byte of the screen buffer address of the content to scroll in
    Context: See this variable in context in the source code
 References: This variable is used as follows:
             * SetBufferAddress uses screenBufferLo


 See screenBufferHi for an explanation of this table.


.screenBufferLo

 EQUB LO(screenBufferRow0 + 0 * 8 - 8)      \ Direction 0
                                            \
                                            \ Pan right, scroll left
                                            \
                                            \ screenBufferRow0 = base address of
                                            \                    screen buffer
                                            \
                                            \ 0 * 8 = the left column (column 0)
                                            \         of the 16-column screen
                                            \ buffer
                                            \
                                            \ -8 = - scrollScreen(Hi Lo)
                                            \    = - +8

 EQUB LO(screenBufferRow0 + 15 * 8 + 8)     \ Direction 1
                                            \
                                            \ Pan left, scroll right
                                            \
                                            \ screenBufferRow0 = base address of
                                            \                    screen buffer
                                            \
                                            \ 15 * 8 = the right column (column
                                            \          15) of the 16-column
                                            \          screen buffer
                                            \
                                            \ 8 = - scrollScreen(Hi Lo)
                                            \   = - -8

 EQUB LO(screenBufferRow0 + 7 * 320 + 320)  \ Direction 2
                                            \
                                            \ Pan up, scroll down
                                            \
                                            \ screenBufferRow0 = base address of
                                            \                    screen buffer
                                            \
                                            \ 8 * 320 = the bottom row (row 7)
                                            \           of the 8-row screen
                                            \           buffer
                                            \
                                            \ 320 = - scrollScreen(Hi Lo)
                                            \     = - -320

 EQUB LO(screenBufferRow0 + 0 * 320 - 320)  \ Direction 3
                                            \
                                            \ Pan down, scroll up
                                            \
                                            \ screenBufferRow0 = base address of
                                            \                    screen buffer
                                            \
                                            \ 8 * 320 = the top row (row 0) of
                                            \           the 8-row screen buffer
                                            \
                                            \ -320 = - scrollScreen(Hi Lo)
                                            \      = - +320