Routines
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9BF3: Count Programs In Sector
Used by the routine at CountSectorPrograms.
Counts the installed programs in a sector of 10 by 10 cells and adds each one to the energy of the sector.
Input
HL Address of the first cell of the sector in the map
HL' Address of the energy of the sector
CountSectorPrograms_Sector 9BF3 LD DE,$0040 Each row of the map is 40 bytes long.
9BF6 LD C,$10 There are 10 rows in the sector.
CountSectorPrograms_Row 9BF8 LD B,$10 There are 10 cells in each row.
9BFA PUSH HL Save the address of the start of the row.
CountSectorPrograms_Cell 9BFB LD A,(HL) Fetch the cell.
9BFC CP $22 Jump if it is an installed program, which is a cell with a current and an initial type of 02.
9BFE JR Z,CountSectorPrograms_Installed
CountSectorPrograms_Next 9C00 INC HL Move on to the next cell.
9C01 DJNZ CountSectorPrograms_Cell Loop back until the whole row has been checked.
9C03 POP HL Restore the address of the start of the row.
9C04 ADD HL,DE Move down to the next row of the map.
9C05 DEC C Count down the rows.
9C06 JR NZ,CountSectorPrograms_Row Loop back until the whole sector has been checked.
9C08 RET Return.
CountSectorPrograms_Installed 9C09 EXX Switch to the shadow registers.
9C0A INC (HL) Add one to the energy of the sector.
9C0B EXX Switch back to the main registers.
9C0C JR CountSectorPrograms_Next Jump back to carry on with the row.
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