Format of APPC/PC "CONVERT" control block:
Offset	Size	Description	)
 00h 12 BYTEs	reserved
 0Ch	WORD	1A00h (verb "CONVERT")
 0Eh  6 BYTEs	00h
 14h	DWORD	(big-endian) return code
 18h	BYTE	conversion
		00h ASCII to EBCDIC
		01h EBCDIC to ASCII
 19h	BYTE	character set
		00h AE
		01h A
		02h G
 1Ah	WORD	length of string to convert
 1Ch	DWORD	pointer to source
 20h	DWORD	pointer to target