HMS Ixxat iPC-I 320, Hardware Manual

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Architecture
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iPC-I 320 Manual, Version 2.8
4.2.1 Program Memory
The program code for the interface can either be loaded into the RAM or directly
executed from the EPROM (depending on the memory mode selected). The
size of the code memory depends on the selected memory mode:
•
Loader/application-mode: 32 kbytes or 63.75 kbytes EPROM as code
memory
•
Von-Neumann-mode: 63 kbytes plus 256 bytes common code and
data memory
•
Harvard-mode: 63 kbytes code memory 256 bytes common
code and data memory
4.2.2 Data Memory
The size of the data memory also depends on the mode selected:
•
Loader/application-mode: 63 kbytes data memory for loadable program
(SW1-8 OFF) becomes the code memory in
Von-Neumann and Harvard mode, 2x56
kbytes data memory (bank-switching, SW1-8
ON)
•
Von-Neumann mode: 56 kbytes plus 256 bytes common memory for
code and data
•
Harvard mode: 56 kbytes data memory plus 256 bytes
common code and data memory
4.2.3 Loader/Application Mode
In the loader/application mode, 32 kbytes and 63.75 kbytes EPROM
respectively are available for the program code. In the EPROM memory, a
loader or an application can be firmly implemented.
As shown in Fig. 4-2 and Fig. 4-3, 56 kbytes of memory are available in the
XDATA area of the controller, in which the application data can be filed. If the
interface is operated in "Disabled toggle" mode (see 3.1.4), the RAM-BANK 1 in
the XDATA area can be displayed by writing a random value in the address
range between FC00h and FCFFh, the RAM-BANK 0 by writing between FD00h
and FDFFh.
Access to the DPRAM, the semaphores and the CAN-controllers (only with
SW1-8 ON) also occurs via XDATA address areas.