Int 14 Fn 0E - Digiboard Digichannel Pc/x* - Write String [S]
AH = 0Eh
CX = number of characters to write
ES:BX -> string
DX = port number (00h-03h) (04h-43h for XAPCM232.SYS)
Return: AX = number of characters actually written
ZF clear if successful
ZF set on error
See Also: AH=0Fh"Digiboard"