BitCount is a shortcut for counting the number of bits set in a byte.
BitCount Mem 0x1234 == Value 6
is the same as
AddSource Bit0 Mem 0x1234 AddSource Bit1 Mem 0x1234 AddSource Bit2 Mem 0x1234 AddSource Bit3 Mem 0x1234 AddSource Bit4 Mem 0x1234 AddSource Bit5 Mem 0x1234 AddSource Bit6 Mem 0x1234 Bit7 Mem 0x1234 == Value 6
and would be true for
0xEE (11101110), etc.
Its most common use is counting collectibles for a Measured condition.
It can be combined with other flags like Delta.
BitCount Mem 0x1234 != BitCount Delta 0x1234
If you just want to make sure all the bits are set and don't need to worry about some subset of bits being set, you should check for concrete values (i.e.
Eight Bit 0x1234 = 0xFF or
Lower4 0x1234 = 0x0F).
WARNING: BitCount always counts all eight bits in a byte. If you only need 6 or 7 bits, you should use the AddSource chain in case the other bits are used for something else.
Last 10 changes on this page:
[2022-07-09 15:18] RALordAndrew:Double-bracket links do not work on docs.retroachievements.org
[2021-04-22 09:12] Jamiras:Updated BitCount Size (markdown)
[2021-04-22 09:06] Jamiras:Updated BitCount Size (markdown)
[2020-05-17 14:09] Jamiras:add BitCount