Entry parameters
Register C = 82H - Alarm set
Register DE = Time descriptor address
10
bytes including message string
address.
Return Parameters
The contents
of
register pair DE are not changed.
TIMDAT (READ ALARM)
Function: Reads the Time Descriptor into the address required. Note
that
the year byte (byte
1)
will contain
FFH
and the seconds byte
(byte 6) contains
FH
in the lowest nibble (lowest 4 bits). This
is
because neither the year nor the Is place
of
the seconds (i.e. it
can only be set in
10
second intervals)
is
relevant for alarm
setting.
Entry parameters
Register C = 84H
Register
DE
= Starting address
to
load the
11
bytes
of
the
Time Descriptor
5.7.9 BIOS Subroutines related to the Serial Port
The Serial
Port
is
not
supported by the BIOS.
5.7.10 BIOS Subroutines related to memory
The memory
of
the PX-8 consists
of
64K bytes
of
RAM and
32K
of
ROM.
By means
of
bank switching it is possible
to
read addresses
OOOOH
to
7FFFH
from either RAM
or
ROM.
In the following routines when references are made to system bank and user
bank they correspond to addresses as follows:
System bank:
OOOOH
to 7FFF (ROM)
8000H to FFFF (RAM)
User bank:
OOOOH
to FFFF (RAM)
5-30
LOADX
is
the entry point for the subroutine which reads 1 byte
of
data from
the specified memory bank.
Entry address: WBOOT
+ 5AH
Entry parameters
Register C = - 1 - System bank
C = 0 - User bank
Register
HL
=
Data
address
Return Parameter
Register A = Data read
This routine does
not
change the contents
of
the other registers.
..
'IIUD
(Ordinarily, this entry
is
not
used by the user.)
STORX
is
the entry point for the subroutine which writes 1 byte
of
data
into
the user bank.
Entry Point: WBOOT
+ 5DH
Entry parameters
Register C = 0 - User bank
Register A =
Data
Register
HL=
Data
address into which
data
is
to
be written;
Return Parameters
This routine will not change the contents
of
the other registers.
.._11;'1
(Ordinarily, this entry
is
not used by the user.)
LDIRX
is
the entry point for the subroutine which transfers data from the speci-
fied memory bank
to
the user bank.
Entry Point: WBOOT
+ 60H
Entry parameters
Register
HL=
Starting address
of
the memory area from which data
is
transferred
5·31
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