feat(buzbee): add command token parsing interface, and help message, added newlines to messages

bbmkhash.c

@@ -36,18 +36,18 @@ int main(void) {
 \n\
   SECTION BBHASHES\n\
 \n\
-  EXPORT BBHASHLEN\n\
+  EXPORT BBCHTC\n\
-  EXPORT BBHASHES\n");
+  EXPORT BBCHT\n");
 
 	/* Command count.
 	* NOTE: This is a u16 because it gets emitted into the output assembly. */
   	uint16_t cCmds = sizeof(s_ppszCmds) / sizeof(char *);
 
 	/* Emit command count */
-  	printf("BBHASHLEN\n  fdb $%.4X\n", cCmds);
+  	printf("BBCHTC\n  fdb $%.4X\n", cCmds);
 
 	/* Emit table data */
-	puts("\nBBHASHES");
+	puts("\nBBCHT");
 	for (int iCmd = 0; iCmd < cCmds; iCmd++) {
 		uint8_t uHash = mkHash(s_ppszCmds[iCmd]);
 		printf("  fcb $%.2X\n", uHash);

src/bbhash.inc

@@ -4,5 +4,5 @@
 
 ; vim: ft=asm
 
-BBHASHLEN IMPORT
+BBCHTC IMPORT
-BBHASHES IMPORT
+BBCHT IMPORT

src/buzbee.s

@@ -2,6 +2,7 @@
 ; Copyright (c) 2025 Gale Faraday
 ; Licensed under MIT
 
+  INCLUDE "bbhash.inc"
   INCLUDE "buzbee.inc"
   INCLUDE "hardware.inc"
   INCLUDE "serial.inc"
@@ -21,9 +22,16 @@ BUZBEE
   bsr INPLOOP ; Fill input buffer.
   cmpy #$0000 ; No data?
   beq BUZBEE  ;  Try again...
-  ; TODO: Parse the input buffer
+  ; TODO: Parse the input buffer into tokens
+  ; TODO: Execute the token buffer
   bra BUZBEE
 
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;;
+;; BUZBEE Input Buffering and Handling Routines
+;;
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
 ; Handle new lines; prints a new prompt and then clears the input buffer
 NEWLINE
   PZSTR PROMPTLINE  ; Print prompt line
@@ -95,6 +103,12 @@ FULLBUF@
   jsr POUTCHAR
   bra INPLOOP
 
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;;
+;; BUZBEE Command Hashing Routines
+;;
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
 ; Makes a hash of four chars in BBIN starting at offset X.
 ; @param X: offset in BBIN to read the four chars from
 ; @return A: resulting hash
@@ -110,34 +124,92 @@ NEXTC@
   bne NEXTC@       ;  No? loop
   rts
 
+; Maps a command hash to a command index, and executes it
+; @corrupts B
+; @param A: input hash
+; @return X: command data table index
+CALLFROMHASH
+  ldx #0          ; Counting up from zero
+NEXTHASH@
+  cmpa BBCHT,x    ; Is this hash our hash?
+  beq CALCPTR@    ;  Yes? skip to next step to put ptr in x
+  leax 1,x        ; Begin considering next hash
+  cmpx BBCHTC     ; Is this the last byte?
+  blo NEXTHASH@   ;  No? try next hash, Yes? fall through
+  PZSTR EM_BADCMD ; Print an error message
+  lbra IFHELP     ; Proceed to call "HELP"
+CALCPTR@
+  tfr x,d         ; Swap into d to do a cheap multiply
+  asld            ; Cheaply << to get *2, pointer size
+  tfr d,x         ; Restore x from d and jump to function at index
+  jmp [BBCMDPTRTBL,x]
+
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;;
-;; BUZBEE Strings and Fixed Data
+;; BUZBEE Internal Command Functions
 ;;
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
-; BUZBEE command hashes resolvable with MKCMDSUM.
+; Print out a help message
-BBCCALL
+IFHELP
-  fcb $E4
+  PZSTR HELP_MSG
-BBCEXEC
+  rts
-  fcb $DB
+
-BBCHELP
+; Placeholder function labels to make assembler happy before git commit
-  fcb $D7
+IFCALL
-BBCPEEK
+IFEXEC
-  fcb $DB
+IFPEEK
-BBCPOKE
+IFPOKE
-  fcb $D1
+IFSREC
-BBCSREC
+  rts
-  fcb $D3
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;;
+;; BUZBEE Strings and Tables
+;;
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+HELP_MSG
+  fcc "-- BUZBEE HELP --"
+  fcb $0D,$0A
+  fcc "Available Commands:"
+  fcb $0D,$0A
+  fcc "CALL <PTR> - Call the pointer given in <PTR> as a subroutine."
+  fcb $0D,$0A
+  fcc "EXEC <PTR> - Start program at <PTR>."
+  fcb $0D,$0A
+  fcc "HELP [CMD] - Display help, command optional."
+  fcb $0D,$0A
+  fcc "PEEK <BASE> [<HIGH>] - Read memory at <BASE> to <HIGH>."
+  fcb $0D,$0A
+  fcc "POKE <ADDR> <BYTES> - Overwrite memory with <BYTES> starting at <BASE>."
+  fcb $0D,$0A
+  fcc "SREC - Enter Motorola S-Record entry mode."
+  fcb $00
+
+BBCMDPTRTBL
+  fdb IFCALL
+  fdb IFEXEC
+  fdb IFHELP
+  fdb IFPEEK
+  fdb IFPOKE
+  fdb IFSREC
 
 PROMPTLINE
   fcb $0D,$0A,$25,$00 ; CR LF '%' NUL
 
 EM_OVERRUN
-  fcn "!!! Overrun Error !!!"
+  fcc "!!! Overrun Error !!!"
+  fcb $0D,$0A,$00
 EM_PARITY
-  fcn "!!! Parity Error !!!"
+  fcc "!!! Parity Error !!!"
+  fcb $0D,$0A,$00
 EM_FRAMING
-  fcn "!!! Framing Error !!!"
+  fcc "!!! Framing Error !!!"
+  fcb $0D,$0A,$00
 EM_FIFO
-  fcn "!!! FIFO Error !!!"
+  fcc "!!! FIFO Error !!!"
+  fcb $0D,$0A,$00
+EM_BADCMD
+  fcc "!!! Bad Command Hash !!!"
+  fcb $0D,$0A,$00