41CL Calculator Manual
© 2019 Systemyde International Corporation
63
0x804088
MMU register for Page 8, Bank 2
0x80408C
MMU register for Page 8, Bank 4
.
.
.
.
0x8040F0
MMU register for Page F, Bank 1
0x8040F4
MMU register for Page F, Bank 3
0x8040F8
MMU register for Page F, Bank 2
0x8040FC
MMU register for Page F, Bank 4
Pages 8-F correspond to the Ports on the calculator, with pages 8-9 being Port 1, pages A-
B being Port 2, and so on as shown below. The MMU entries for these pages are
automatically handled by
41CL Extra Functions
, so only the MMU entries for Page 4
needs to be manually programmed.
Port
Half
Page Address
PLUG function
N/A
N/A
6
PLUGP
N/A
N/A
7
PLUGH
Lower
8
PLUG1L
1
Upper
9
PLUG1U
PLUG1
Lower
A
PLUG2L
2
Upper
B
PLUG2U
PLUG2
Lower
C
PLUG3L
3
Upper
D
PLUG3U
PLUG3
Lower
E
PLUG4L
4
Upper
F
PLUG4U
PLUG4
Pa
ge
4
i
s
s
pe
c
i
a
l
t
o
t
he
OS,
a
nd
onl
y
a
f
e
w
ROM
i
ma
ge
s
c
a
n
be
us
e
d
i
n
i
t
.
I
f
you
don’
t
know
wha
t
you
a
r
e
doi
ng,
don’
t
t
r
y
t
o
us
e
Pa
ge
4.
Pa
ge
6
i
s
nor
ma
l
l
y
us
e
d
by
a
pr
i
nt
e
r
and Page 7 is used by HP-
I
L,
s
o
don’
t
t
r
y
t
o
us
e
e
i
t
he
r
of
t
he
s
e
pa
ge
s
unl
e
s
s
you
don’
t
need access to a printer or HP-IL.
Pages 0-3 and 5 contain the OS for the machine, so the MMU entries for these pages are
normally not used.
The contents of an MMU memory location are used as follows:
bit
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
EN LCK
MULTI
A23 A22 A21 A20 A19 A18 A17 A16 A15 A14 A13 A12
