GSC Item modifying box codes

Set first item pocket item quantity to 144:

1st
1 - xor A - AF                  // A = 0
2-3 - or A, 90 - F6 90          // A = 90
4-6 - LD (F894), A - EA 94 F8   // (F894) = 90
7 - RET NC - D0                 // Return

// Converted to pokémon letters.
p0QéU2'd

Set first item pocket item quantity to 255:

1st
1 - xor A - AF                  // A = 0
2-3 - or A, FF - F6 FF          // A = FF
4-6 - LD (F894), A - EA 94 F8   // (F894) = FF
7 - RET NC - D0                 // Return

// Converted to pokémon letters.
p09éU2'd

Set first item pocket item to 8B(Berry Juice):

1st
1 - xor A - AF                  // A = 0
2-3 or A, 8B - F6 8B            // A = 8B
4-6 - LD (F893), A - EA 93 F8   // Write A to F893(D893)
7 - RET NC - D0                 // Return

// Converted to pokémon letters.
p0LéT2'd

Increment first item in bag:
1 - xor A - AF                  // A = 0
2-3 - or A, 81 - F6 81          // A = 81
4-5 - sub A, 80 - D6 80         // A = 80
6 - push AF - F5                // A = 0
7 - pop HL - E1                 // H = 1
8 - xor A - AF                  // A = 0(it already was 0 but we needed filler :P)
2nd
1-3 - LD A, (F893) - FA 93 F8   // A = (F893)
3rd
1 - ADD A, H - 84               // A = (F893)+1
4th
1-3 - LD (F893), A - EA 93 F8   // (F893) = (F893)+1
4 - xor A - AF                  // A = 0 && carry = 0
5 - RET NC - D0                 // Return

// Converted to pokémon letters.
p0B'vA(Female)(PK)p
4T2
E
éT2p'd

Decrement first item in bag(fill names with 5 first):
1 - xor A - AF                  // A = 0
2-3 - or A, 81 - F6 81          // A = 81
4-5 - sub A, 80 - D6 80         // A = 80
6 - push AF - F5                // A = 0
7 - pop HL - E1                 // H = 1
8 - xor A - AF                  // A = 0(it already was 0 but we needed filler :P)
2nd
1-3 - LD A, (F893) - FA 93 F8   // A = (F893)
3rd
1 - SUB A, H - 94               // A = (F893)-1
4th
1-3 - LD (F893), A - EA 93 F8   // (F893) = (F893)-1
4 - xor A - AF                  // A = 0 && carry = 0
5 - RET NC - D0                 // Return


// Converted to pokémon letters.
p0B'vA(Female)(PK)p
4T2
U
éT2p'd