The Hobbit (v1.0): Routine at 7F3D

7F3D: Parser: fetch the next token

Reads the next token from the token buffer (pointer at $B5CD), which it then advances by two. On return D holds the class (the top nibble of the first byte) and BC the word: B the top nibble of the offset and C the bottom byte. The previous class is saved at $B5CF (so that handlers can see what came before), and the position of the token is saved at B5CB for error messages. A also holds the class.

Output
A	Class
D	Class
BC	Word

7F3D

LD HL,($B5CD)

HL = the token pointer

7F40

LD ($B5CB),HL

Remember where this word is, for error messages

7F43

LD A,D

Remember the previous class

7F44

LD ($B5CF),A

7F47

LD A,(HL)

B = the top four bits of the word offset

7F48

AND $0F

7F4A

LD B,A

7F4B

LD A,(HL)

D = A = the class

7F4C

AND $F0

7F4E

LD D,A

7F4F

INC HL

7F50

LD C,(HL)

C = the bottom eight bits of the offset

7F51

INC HL

7F52

LD ($B5CD),HL

Move the token pointer on

7F55

RET