Acorn BBC Master 65C102, Руководство пользователя

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The *CONFIGURE command
The *CONFIGURE command may be used to enable and disable the TUBE
communications. It may also be used to select between internal and
external TUBE communication. To enable or disable the TUBE
communication, *CONFIGURE with TUBE or NOTUBE respectively may be
used.
To allow you to add an external co-processor, sometimes referred to as
a second processor, you may switch from using the internal TUBE to
the external TUBE. This is also carried out using the *CONFIGURE
command, this time with INTUBE and EXTUBE respectively.
For further information on the *CONFIGURE command see the REFERENCE
MANUAL Part 1.
SYSTEM MEMORY
The following information explains the way in which the memory of
both the I/O processor and the co-processor are configured. It is
only intended as a general introduction to the memory usage of the
two processors. For a more full explanation of the way in which the
memory is configured please refer to the REFERENCE MANUAL.
Please note that whilst a general understanding of the systems'
memory configuration may be of use, it is by no means essential.
Figure 2 shows the memory map for the I/O processor when it is
working with the 65C102 co-processor.
DISTINGUISHING BETWEEN MEMORIES
You will have noticed from the memory map that both the I/O processor
and the co-processor are numbered from &0000 to &FFFF. With the co-
processor working, the various filing systems must have a way of
distinguishing between the two memories in order to SAVE or LOAD
programs into the correct place. This is done by defining the co-
processor memory as running from &0000 to &FFFF, and the I/O processor
memory from &FFFF0000 to &FFFFFFFF.
For example, memory location &C000 resides, by definition, in the co-
processor: memory location &FFFFC000 resides in the I/O processor.
Suppose you run a machine-code program which resides in the co-
processor from memory location &6000 to &6500. This program draws a
pretty picture on the screen in MODE 1, and you would like to save
both the program and the resulting picture onto disc.
To save the program onto disc, you would type:
*SAVE GRAFPRG 6000 6500 <RETURN>
where GRAFPRG is the filename you have chosen. To load and run the
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