Function Name: SETBNK

Purpose: Set bank for I/O operations
Call address: $FF68 (hex) 65384 (decimal)

	Registers:	.A = BA, memory bank (0-15)
			.X = FNBANK, filename bank
	Memory:		system map
	Flags:		none
	Calls:		SETNAM
	Registers:	none
	Memory:		BA, FNBANK updated
	Flags:		none

Description: SETBNK is a prerequisite for any memory I/O operations, and must be used along with SETLFS and SETNAM prior to OPENing files, etc. BA ($C6) sets the current 64KB memory bank for LOAD/SAVE/VERIFY operations. FNBANK ($C7) indicates the bank in which the filename string is found. The Kernal routine GETCFG is used to translate the given logical bank numbers (0-15). SETBNK is often used along with SETNAM and SETLFS calls prior to OPEN's. See the Kernal OPEN, LOAD and SAVE calls for examples.