Volex TTX2000 S Issue 1.2: Routine at 1966

1966: write_header_message: Copy up to 16 bytes from address in DE to row 0 in page display buffer.

Used by the routines at telesoftware_main and display_message.
write_header_message	1966	CALL clear_header_start	Clear 16 characters of header to spaces.
	1969	LD HL,(page_display_buffer_pointer)	Load address of page display buffer and add 8 to move to start of page header.
	196C	LD BC,$0008
	196F	ADD HL,BC
	1970	LD B,$20	Set B to 16 as a loop counter.
write_header_message_0	1972	LD A,(DE)	Load next character from string in DE.
	1973	CP $24	Return if character is '$'.
	1975	JR Z,write_header_message_1	Return if character is '$'.
	1977	LD (HL),A	Else copy character to string in HL and advance string pointers.
	1978	INC DE
	1979	INC HL
	197A	DJNZ write_header_message_0	Loop through up to 16 characters then return.
write_header_message_1	197C	RET	Loop through up to 16 characters then return.