pokemon gold backup bg palette copy

0x3557: LD A, 0xE4
        CALL 0x0C61

        LDH BGP, A      ; Stores 0xE4 in BGP
        PUSH AF
        LDH A, 0xFFE8   ; The value at this address is 0x01, unsure of it's significance
        AND A
        JR Z, + 0x18    ; Jump not taken
        PUSH HL
        PUSH DE
        PUSH BC
        LD HL, 0xC280   ; In the render loop, Pokemon Gold copies 64 bytes starting at 0xC280 into BG palette ram
        LD DE, 0xC200   ; In the loop below, it copies 64 bytes offset from 0xC200 into the 0xC280 region
        LDH A, BGP      ; Reads value stored in BGP into A, even in CGB mode
        LD B, A
        LD C, 0x08
        CALL 0x0CEA

loop0:  PUSH BC         ; Store outer loop counter
        LD C, 0x04
loop1:  PUSH DE
        PUSH HL         ; Stores the pointer into the backup palette ram region
        LD A, B         ; On the first iteration, B holds the value in BGP
        AND 0x03
        ADD A, A
        LD L, A         ; The game uses the shifted BGP as an offset from 0xC200 to copy values from there into the
                        ; backup palette region
        LD H, 0x00
        ADD HL, DE
        LD E, (HL)
        INC HL
        LD D, (HL)
        POP HL          ; Retrieves the pointer into the backup palette ram region
        LD (HL), E
        INC HL
        LD (HL), D
        INC HL
        SRL B
        SRL B           ; Right shifts the BGP value twice
        POP DE
        DEC C
        JR NZ, loop1
        LD A, 0x08
        ADD A, E        ; Increments the pointer which intitially pointed to 0xC200
        JR NC, skip
        INC D
skip:   LD E, A
        POP BC          ; After 4 inner loop iterations, the value of BGP has been shifted out of B. Here, the
                        ; original value of BGP is popped back in.
        DEC C
        JR NZ, loop0