Sharp MZ-5500 User Manual

6-3 I/O bit map
(1) System board
DEVICE ADD
8255
010H
[ G,,"pA,
Mode 1
Group B
Mode
0
011H
,
012H
(013H)
NOTES:
BIT
PAO
PAl
PA2
PA3
PA4
PA5
PA6
PA7
PBO
PB1
PB2
PB3
PB4
PB5
PB6
PB7
PCO
PC1
PC2
PC3
PC4
PC5
PCS
PC7
SIGNAL NAME
DATA1
DATA~
DATA3
DATA4
~
DATA6
DATA7
DATAB
BUSY
PE
PDTR
OK
SRK
CD
"Cl"
MOTOR ON
DC
STC
EXCLK EN
IR-PRT
STROBE
ACK
1) Group A
is used in Mode 1.
2) Group B
is used in Mode o.
Table 16
1/0
Data output to Centronics I/F (negative polarity).
OUT
Null codes are hex FF.
Centronics
I/F bu~~y if zero.!
Centronics
I/F.
Centronics I/F select signal (selects if one.)
Data bit from keyboard
} Key
IN
OutpUt requested from keyboard
Called signal }
BSC transmission
Carrier
sense
UFO motor on status input
OUT
Data bit to keyboard }
OUT
Strobe to keyboard
OUT
BSC external dock (BSC if High)
OUT Interrupt by ACK input to Centronics I/F.
OUT Cantronics I/F STROBE output (-U-!
IN
Centronics IIF ACK input
OUT
Not used.
3) The desired
bit of the output to Group C may be set or reset USing the control register (013H).
4) The bit PC6 is an interrupt enable flag IINTE), and is set or reset by the CPU.
AFTER
PlO
Input
mode
(FFH)
Mode
input
Input
mode
(FFH)
5) While the ACK may
be read by PC3, is needs not be reed as its status is known to the CPU via the PlC.
Table 17
1/0
AFTER
DEVICE
ADD BIT SIGNAL NAME
PlO .
AY·3-8912
230H
(Sound IC)
Input
OUT
Drive motor on signal (on if Low.!
IOA4 MOTOR ON
mode
IOA5
MAO
} A<N IAOOOOH-BFFFFHI book "I"" ",00'
(FFH)
10A6
MA1
IOA7 MA2
PORT·A
060H
100
High Den
(LS541 )
101
RSTSW
RESET
switch input (on if zero! +- MFD selection
102
DIP
SW1 SW1
SW2
l
Input
103 DIP sm
IN
System DIP switches
mode
104 DIP SW3
SW3
(see next page)
105
DIP
SW4
SW4
106
DIP
SWS
SW5
1D7
DIP SW6 SW6
-00-
INITIAL
DEFAULT
Output
mode
(FFH)
Mode
input
1
0
0
0
0
1
X
X
INITIAL
DEFAULT
0
0
0
0
1
0
0
Input
mode
'I

Sharp MZ-5500 Specifications

General

Brand	Sharp
Model	MZ-5500
Category	Desktop
Language	English