CMDLOOP:
		; Receive command safely, EXCEPT zero word
		CALL REC_BYTE
		CMP R14,#0
		JMPR CC_NE,CMDLOOP_ERROR
		CMP R15,#CMD_PING
		JMPR CC_NE,CMDLOOP_NO_PING
		; Respond to ping
		MOV R15,#SHELL_ACK
		CALL SEND_BYTE
		JMP CMDLOOP		
CMDLOOP_NO_PING:
		MOV R13,#SEND_BYTE
		MOV R12,#REC_BYTE
		CALL ACK_DATA
		CMP R14,#0
		JMPR CC_EQ,CMDLOOP_OK
CMDLOOP_ERROR:
		MOV R15,R14
		CALL SEND_BYTE
		JMP CMDLOOP
CMDLOOP_OK:
		PUSH R15
		MOV R15,#0
		CALL SEND_BYTE ; Send zero byte
		POP R15 ; Restore command number

		CMP R15,#CMD_ERASE_BLOCKS
		JMPR CC_NE,CMDLOOP_1
		CALL ERASE_BLOCKS
		JMP CMDLOOP
CMDLOOP_1:
		CMP R15,#CMD_READ
		JMPR CC_NE,CMDLOOP_2
		CALL READ
		JMP CMDLOOP
CMDLOOP_2:
		CMP R15,#CMD_WRITE
		JMPR CC_NE,CMDLOOP_3
		CALL WRITE
		JMP CMDLOOP		
CMDLOOP_3:
		CMP R15,#CMD_IDENTIFY
		JMPR CC_NE,CMDLOOP_4	
		CALL IDENTIFY
		JMP CMDLOOP
CMDLOOP_4:
		CMP R15,#CMD_ERASE_CHIP
		JMPR CC_NE,CMDLOOP
		CALL ERASE_CHIP
		JMP CMDLOOP