Sharp MZ-80B User manual

Personal Computer
. lllZ·OOrnJ
MONITOR SB-1510
REFERENCE MANUAL
SHARP
•

J
SHARP
Personal Computer
MZ-808
Monitor SB-1510 Reference Manual
· ~ .
january 1981
080231-150281
Printed in Japan
©SHARP CORPORATION

NOTICE
This manual is applicable to the MONITOR S8-1510 system software used with the
SHARP MZ - 808 Personal Computer. The MZ - 808 general-purpose personal computer is
supported by system software which is filed in software packs (cassettes and diskettes).
All system software is subject to revision without prior notice; therefore, you are
requested
to pay special attention to their file version numbers.
This manual has been carefully prepared and checked
for completeness, accuracy and
clarity. However, in the event that you should notice any errors or ambiguities, please feel
free to contact your local Sharp representative for clarification.
All system software packs provided for the MZ-808 are original products, and all rights
are reserved. No portion
of any system software pack may be copied without approval of
the Sharp Corporation.
ii

Introduction
This manual describes commands and subroutines of standard system software MONITOR SB-151 0
for the Sharp MZ-80B and procedures for coding machine language programs and generating data.
MONITOR SB-1510 is part of the system software for the MZ-80B and it acts mainly as the moni-
tor program for BASIC SB-5 510, DISK BASIC SB-651 0 and Double Precision DISK BASIC SB-671 0.
Further, MONITOR SB-1510 can be used as a machine language monitor by transferring system con-
trol to it. With this feature, you can not only code and debug machine language programs but also
generate system programs
of your own.
This manual includes all MONITOR SB-1510 assembly listings for reference.
iii
•., .

Contents
Notice .... ...... .... ......... . .............. .. .... . .............. ii
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. ....... ..... iii
Chapter 1 MONITOR SB-1510 Commands and Subroutines ................ 1
1.1 Function of the monitor program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.2 Using
monitor commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.2.1
1.2.2
1.2.3
1.2.4
.. ;.
1.2.5
1.2.6
M command
.. . ..... ..... .. . .......................... . 4
D command ........................ . .. . .- ...... . .... . .. 7
J command ... ... .... ... ... . ........................... 9
S command
V command
L command
....... ... . .. . .. ... .. .. . ............ . .... . 10
....... . .................................. 12
13
1.3 Monitor Subroutines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Appendix ....................................................... 21
A.l Mnemonic Codes and Corresponding Object Codes . . . . . . . . . . . . . . . . . . 22
(Mnemonic codes are arranged in alphabetic order.)
A.2 Object Codes and Corresponding Mnemonic Codes
............... ... 32
(Object codes are arranged in hexadecimal order.)
A.3 MONITOR SB-1510 Assembly Listing
.. ............ ..... .. . .. .. . 42
iv

Chapter 1
MONITOR SB-1510 Commands and Subroutines
This chapter describes six commands executed at the monitor command level and monitor sub-
routines enables the user to generate, execute and/or file a simple machine language program; that is,
to operate the MZ-80B at the CPU level. Machine language programs generated can be linked with
other BASICprograms with the USR function
of the BASIC language.
I

2
1.1 Function of the monitor program
A Monitor program generally monitors system programs such as the BASIC interpreter. The MZ-
80B uses a Monitor program called MONITOR SB-1510.
It includes various functional subroutines
which control
the keyboard, display, sound circuit, cassette tape deck, etc. These subroutines are
called
by the BASIC interpreter when it executes INPUT statement, SAVE command, MUSIC state-
ment or other commands or statements. Monitor subroutines may also be called by the user at will.
$0000
$1220
MONITOR
BASIC interpreter, etc.
User's program
$FFFF ...._ _______ __,
FIGURE 1.1 Monitor subroutine call
1/0 control: keyboard, CMT, TV, etc.
Return
MONITOR SB-1510 occupies 4.5K bytes of memory and is stored in memory addresses $0000
through $121F. Its required work area is included within this area. Therefore, MONITOR SB-1510
can be used as an individual system program. That is, it can perform the following functions in addi-
tion
to system monitoring.
• It generates, executes and files machine language programs using 6 monitor commands:
M: Memory correction
D:
Memory dump
J
Jump
s -save
V:
Verify
L:
Load

3
• Since MONITOR SB-1510 is stored in RAM, its contents may be varied with commands. For
example, the contents of $0000- $0038 and $0066, which are called when processing an inter-
rupt, can be changed at will
or the function of a monitor subroutine can be modified.
Programs may be freely written
on cassette tape, so a machine language program including MONI-
TOR SB-1510 can be filed for future use. See the assembly listing for MONITOR SB-1510 in Ap-
pendix A.3.
To use monitor commands, system control must be transferred
to the Monitor from the BASIC
interpreter or other system program.
• To transfer system control from the BASIC interpreter to the Monitor, execute a MON command.
• To transfer system control from the Assembler or Linkert to the Monitor, execute a ! command.
• To transfer system control from the PASCAL interpretertt to the Monitor, execute an editor _
command,
Q/.
FIGURE 1.2 shows a display flame when a BASIC command MON is executed. After the MON
command has been executed, the cursor moves to the next line, an asterisk at the beginning of the new
line and the cursor flickers to inform the operator
that system control has been transferred to the
Monitor.
FIGURE 1.2 Execution of a BASIC command MON
t. tt. Refer to the Assembler, Linker and PASCAL interpreter manuals.

4
1.2 Using monitor commands
General conventions for use of Monitor commands are as follows:
• Commands and data are input from the keyboard with the I CR ] key pressed to conclude the
entry.
• Data display and input are in hexadecimal. One byte of data consists of two hexadecimal digits
and an address consists
of four hexadecimal digits.
• When the number of characters input firm the keyboard exceeds the number the required by the
Monitor program, the excess are ignored.
• To cancel execution of a command, press the IBREAK] key.
• Every command can access any memory location, allowing a wide range of applications, but spe-
ci~l care must be taken not to destroy required data or a program.
1.2.1 M command·
Function
Operation
Corrects the contents of the specified memory address.
When
aM command is entered, the display is as shown in FIGURE 1.3.
FIGURE 1.3

5
In this case, the Monitor requests the operator to enter the address at which mem-
ory correction
is to start.
For example, let memory correction start at memory address $70AO. Enter 70AO
from the keyboard, then press the [ CR ] key. The display is as shown in FIGURE
1.4.
FIGURE 1.4
The monitor program displays the contents, $00, of memory address $70AO and
requests the operator to determine whether or not the contents of$ 70AO are to be
corrected.
To correct them, enter two hexadecimal digits, from of 00 to FF, at the
cursor position from the keyboard. For example, to change the contents of $70AO
from $00 to $C9 (operation code of the RET command), enter "C9", then press
the [ CR ] key.
The monitor program then corrects the contents of the memory address and the
display is as shown in FIGURE 1.5.
FIGURE 1.5