User`s manual

6 PCL-848AB User's Manual
2.2.2. Firmware Address Setting
The IBEE-488 interface driver routine is stored in the on-board i EPROM. The
memory address of this firmware can be selected by SW2. The memory segment of
the firmware can be from hex 8000 to s hex FC00. Factory setting is hex D000.
The range of these locations is out of the 640K system memory of i the IBM PC, PC/
XT and PC/AT. However, choice of this location must be made to avoid any conflict
with other interface cards. When two or more IEEE-488 interface cards are used in one
PC, the location settings must be different in order to have different working space
although the firmware code is the same.
The SW2 positions l to 5 determine the address bits Al8 to Al4. ~ Address bit A19 is
always 1. Address bits below A13 (included) are not cared.
Memory Location Segment SW2-1 SW2-2 SW2-3 SW2-4 SW 2-5
(hex) A18 Al7 A16 A15 A14
-----------------------------------------------------------------------------------------------------
8000 0 0 0 0 0
8400 0 0 0 0 1
8800 0 0 0 1 0
.
.
Reserved A000 0 1 0 0 0
.
.
CRT Display B000 0 l 1 0 0
.
.
Factory Setting D000 1 0 1 0 0
.
.
System ROM F000 1 1 1 0 0
FC00 1 1 1 1 1
---------------------------------------------------------------------------------------
* 0 : ON l : OFF
This multifunction IEEE-488 interface card takes 10K bytes of the memory space
including 8K byte RON and 2K byte RAM. The starting . address of the working
RAM is offset 8K bytes from the ROM starting address.