ld a, d
    cp $00 ; is the flag id > 256?
    jr z, .start ; no
    jr c, .read ; yes
    jr .invalid ; some weird state of both yes and no??
.start
    ld a, e
    cp $a2 ; $1a2 flag entries
    jr c, .read
.invalid
    xor a
    ld e, a
    ld d, a
.read
    ld hl, Flags
    add hl, de ; skip three
    add hl, de ; bytes per
    add hl, de ; flag
    ld e, [hl]
    inc hl
    ld d, [hl]
    inc hl
    ld c, [hl] ; flag bit
    ld a, b
    cp $01
    jr c, .reset ; b = 0
    jr z, .set   ; b = 1
    ld a, [de]   ; b > 1
    and c
    ld c, a
    ret
.set
    ld a, [de]
    or c
    ld [de], a
    ret
.reset
    ld a, c
    cpl ; AND all bits except the one in question
    ld c, a
    ld a, [de]
    and c
    ld [de], a
    ret
; 80462

Flags: ; 80462
    dwb $d957, %00000010
    dwb $d957, %00000001
    dwb $d957, %00000100
    dwb $d957, %00001000
    dwb $d957, %10000000

    dwb $def5, %01000000
    dwb $def5, %00000001

    dwb $df2c, %00000001

    dwb $d854, %00000001
    dwb $d854, %10000000

    dwb $dc39, %00000001

    dwb $d84c, %00000001
    dwb $d84c, %00000010
    dwb $d84c, %00001000
    dwb $d84c, %00010000
    dwb $d84c, %01000000
    dwb $d84c, %10000000

    dwb $d84d, %00000100 ; bug catching contest timeup
    dwb $d84d, %00000010
    dwb $d84d, %00000001
    dwb $d84d, %00010000
    dwb $d84d, %00100000
    dwb $d84d, %01000000
    dwb $d84d, %10000000

    dwb $dbf5, %00000001
    dwb $dbf5, %00000010
    dwb $dbf5, %00000100 ; downhill (cycling road)

    ; johto badges
    dwb $d857, %00000001 ; $1b
    dwb $d857, %00000010 ; $1c
    dwb $d857, %00000100 ; $1d
    dwb $d857, %00001000 ; $1e
    dwb $d857, %00010000 ; $1f
    dwb $d857, %00100000 ; $20
    dwb $d857, %01000000 ; $21
    dwb $d857, %10000000 ; $22

    ; kanto badges
    dwb $d858, %00000001 ; $23
    dwb $d858, %00000010 ; $24
    dwb $d858, %00000100 ; $25
    dwb $d858, %00001000 ; $26
    dwb $d858, %00010000 ; $27
    dwb $d858, %00100000 ; $28
    dwb $d858, %01000000 ; $29
    dwb $d858, %10000000 ; $2a

    dwb $def3, %00000001
    dwb $def3, %00000010
    dwb $def3, %00000100
    dwb $def3, %00001000
    dwb $def3, %00010000
    dwb $def3, %00100000
    dwb $def3, %01000000
    dwb $def3, %10000000

    dwb $dca5, %00000001
    dwb $dca5, %00000010
    dwb $dca5, %00000100
    dwb $dca5, %00001000
    dwb $dca5, %00010000
    dwb $dca5, %00100000
    dwb $dca5, %01000000
    dwb $dca5, %10000000

    dwb $dca6, %00000001
    dwb $dca6, %00000010
    dwb $dca6, %00000100
    dwb $dca6, %00001000
    dwb $dca6, %00010000
    dwb $dca6, %00100000
    dwb $dca6, %01000000
    dwb $dca6, %10000000

    dwb $dca7, %00000001
    dwb $dca7, %00000100
    dwb $dca7, %00001000
    dwb $dca7, %00010000
    dwb $dca7, %00100000
    dwb $dca7, %01000000
    dwb $dca7, %10000000

    dwb $dca8, %00000001
    dwb $dca8, %00000010
    dwb $dca8, %00000100
    dwb $dca8, %00010000

    dwb $dc9d, %00000001
    dwb $d84d, %00001000

    dwb $dc1e, %00000001
    dwb $dc1e, %00000010
    dwb $dc1e, %00000100
    dwb $dc1e, %00001000
    dwb $dc1e, %00010000
    dwb $dc1e, %00100000
    dwb $dc1e, %01000000
    dwb $dc1e, %10000000

    dwb $dc1f, %00000001
    dwb $dc1f, %00000010
    dwb $dc1f, %00000100
    dwb $dc1f, %00001000
    dwb $dc1f, %00010000
    dwb $dc1f, %00100000
    dwb $dc1f, %01000000
    dwb $dc1f, %10000000

    dwb $dc20, %00000001
    dwb $dc20, %00000010

    dwb $cfbc, %10000000
    dwb $d472, %00000001 ; 0 if boy, 1 if girl
    dwb $dbf3, %00000100

    dwb $dc4c, %00000001
    dwb $dc4c, %00000010
    dwb $dc4c, %00000100
    dwb $dc4c, %00001000
    dwb $dc4c, %00010000
    dwb $dc4c, %00100000
    dwb $dc4c, %01000000
    dwb $dc4c, %10000000

    dwb $dc4d, %00000001
    dwb $dc4d, %00000010
    dwb $dc4d, %00000100
    dwb $dc4d, %00001000
    dwb $dc4d, %00010000
    dwb $dc4d, %00100000
    dwb $dc4d, %01000000
    dwb $dc4d, %10000000

    dwb $dc4e, %00000001
    dwb $dc4e, %00000010
    dwb $dc4e, %00000100
    dwb $dc4e, %00001000
    dwb $dc4e, %00010000
    dwb $dc4e, %00100000
    dwb $dc4e, %01000000
    dwb $dc4e, %10000000

    dwb $dc50, %00000001
    dwb $dc50, %00000010
    dwb $dc50, %00000100
    dwb $dc50, %00001000
    dwb $dc50, %00010000
    dwb $dc50, %00100000
    dwb $dc50, %01000000
    dwb $dc50, %10000000

    dwb $dc51, %00000001
    dwb $dc51, %00000010

    dwb $dc54, %00000001
    dwb $dc54, %00000010
    dwb $dc54, %00000100
    dwb $dc54, %00001000
    dwb $dc54, %00010000
    dwb $dc54, %00100000
    dwb $dc54, %01000000
    dwb $dc54, %10000000

    dwb $dc55, %00000001
    dwb $dc55, %00000010
    dwb $dc55, %00000100
    dwb $dc55, %00001000
    dwb $dc55, %00010000
    dwb $dc55, %00100000
    dwb $dc55, %01000000
    dwb $dc55, %10000000

    dwb $dc56, %00000001
    dwb $dc56, %00000010
    dwb $dc56, %00000100
    dwb $dc56, %00001000
    dwb $dc56, %00010000
    dwb $dc56, %00100000
    dwb $dc56, %01000000
    dwb $dc56, %10000000

    dwb $d45b, %00000100
    dwb $dc20, %00000100
    dwb $dc20, %00001000 ; $a2
; 80648