41CL User Manual
© 2019, Systemyde International Corporation
18
Initial Software Configuration
The 41CL includes a set of functions that provide access to the new features of the
NEWT microprocessor. When power is first applied or when the calculator is reset,
resulting in the
MEMORY LOST
message, the
41CL Extra Functions
are mapped to
Page 7 to allow you to do the initial configuration of the calculator. This Page 7 mapping
is enforced by the hardware for as long as the Memory Management Unit (MMU) is
disabled.
During the initial configuration the
41CL Extra Functions
must either be moved else-
where so that Page 7 can be used by HP-IL Peripherals or the Page 7 entries in the MMU
must be programmed to point to the
41CL Extra Functions
after the MMU is enabled.
Until the
41CL Extra Functions
are moved from Page 7 HP-IL will not be available, and
an HP-IL Module should not be inserted into the calculator because this will lead to bus
conflicts.
The
41CL Extra Functions
(YFNZ mnemonic) uses XROM #15. If this is going to
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section later in this document. Note that some third-party software (CL Utilities, for
example) requires the use of the XROM #15 version of the
41CL Extra Functions
.
The
41CL Extra Functions
image resides in an area of Flash memory that is protected
from modification, so that it should always be available.
As you become more familiar with the 41CL, you may prefer to use the
41CL Extreme
Functions
(YFNX mnemonic), which provides a more convenient user interface that
prompts for user input.
The minimum sequence for the initial configuration uses three
41CL Extra Functions
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features of the 41CL this is sufficient for the initial configuration. This sequence is:
1.
XEQ ALPHA
MMUCLR
ALPHA
initializes all of the MMU entries in memory, mak-
ing it safe to enable the MMU in the third step.
2.
ALPHA
YFNZ
ALPHA XEQ ALPHA
PLUG1L
ALPHA
plugs the
41CL Extra
Functions
into the lower half of Port 1 (which is Page 8). Since the MMU is still dis-
abled this has no effect yet. Note that any port can be used for the
41CL Extra Func-
tions
. Plugging the
41CL Extra Functions
into a Port allows the use of HP-IL.
Or you can use
ALPHA
YFNZ
ALPHA XEQ ALPHA
PLUGH
ALPHA
to plug the
41CL Extra Functions
into Page 7. This saves half of a Port, but means that HP-IL
(including an HP-IL printer) will not be available. Since the MMU is still disabled
this has no effect yet.