Download MPA Multi-Protocol Terminal Emulation Adapter Using the DP8344

TL/F/10488 – 1
FIGURE 1-1. Block Diagram of Typical BCP System
To support the IBM interface mode, the MPA-II utilizes an 8k
block of dual-port RAM. This RAM must be located somewhere in the PC’s memory space. The default location in PC
memory is CE000. This location can be relocated by writing
the upper 8k byte boundary to I/O location 2D7h or by using
the MPA-II Loader program (LD).
The I/O space requirements, for any interface mode, are
the total of the I/O space requirements for the MPA-II.
This means that the I/O locations 220h – 22Fh and 2D0h –
2DFh are required for the MPA-II.
For execution space, the LD requirements are minimal (less
than 64k). The amount of free RAM available for a PC emulator depends on the particular emulation package (i.e., E78,
EMU, or IBM PC 3270, etc . . . ). The MPA-II system does
not use any resident software of its own accord.
In summary, the Multi-Protocol Adapter II Design/Evaluation
Kit contains the hardware, software and the MPA-II System
User Guide and Technical Reference to aid designers in
development of peripheral devices and network interfaces
based on the DP8344. The following items are not included
in the MPA-II system and therefore MUST be provided by
the user to use the MPA-II in a live terminal emulation session:
Ð IBM PC XT/AT or compatible
Ð PC-DOS version 3.0 or higher
Ð PC emulation software such as DCA’s E78 for MPA-II
IRMA interface mode, one of IBM’s PC 3270 emulation
programs for MPA-II IBM interface mode, DCA’s EMU
for MPA-II ALEC interface mode, or any of the third party
vendors which support either the IRMA, IBM or ALEC
emulation card interface modes, including SIMPC MASTER by SIMWARE, RELAY Gold by RELAY Communications, and CrossTalk MK.4 by DCA.
2.0 OPERATION
System Requirements
THE MPA-II system implements both 3270 and 5250 terminal emulation using the DCA and IBM industry standard interfaces. Note that the MPA-II system emulates the hardware and link-level firmware portion of the DCA and IBM
interfaces. This allows the MPA-II system to run with a variety of emulators. For example, the DCA emulator system for
the 3270 environment is called IRMA. IRMA consists of a
full sized PC board along with its link-level firmware, and the
PC emulator software ‘‘E78.EXE’’. The MPA-II system replaces the IRMA PC board and its link-level firmware.
Therefore, the MPA-II system, when configured correctly,
appears in every way to the emulator, E78, to be the actual
IRMA hardware/link-level firmware portion of the DCA emulator system for the 3270 environment. Thus to operate the
MPA-II system in a live communication system, a PC emulation program is required; for example DCA’s E78.EXE. In
DCA interface modes the emulators are: ‘‘E78’’, for the
3270 IRMA system; and ‘‘EMU’’, for the 5250 Smart Alec
system. In the IBM interface mode the emulators are
‘‘PC3270’’ for the 3270/3299 CUT environment and
‘‘PSCPG’’ for the 3270/3299 DFT environment. Any emulator compatible with one of the emulators listed above can
be used to achieve terminal emulation using the MPA-II system.
The system requirements for using the MPA-II are dependent upon which interface the MPA-II is emulating. In DCA
interface modes, a PC interrupt is not used. However, in the
IBM interface mode, a PC interrupt is required. The PC interrupt level is selected as follows: IRQ2 is selected with jumper JP6; IRQ3 by jumper JP4; and IRQ4 by jumper JP5. The
factory configuration selects the PC interrupt level IRQ2.
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