Address |
R/W |
Detail
|
$FD00
|
R
|
Keyboard data high bit, and clock speed indicator
Bit |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
0
|
Name
|
D8
|
|
CLK
|
D8
|
Keyboard data bit 8
|
|
CLK
|
Clock speed
|
0: 1.2MHz 1: 2MHz AV always reads '1'
|
|
W
|
Audio cassette and printer
Bit |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
0
|
Name
|
SLCTIN
|
STRB
|
|
CASRMT
|
CASWR
|
SLCTIN
|
Printer select input
|
0: Select 1: Unselect
|
STRB
|
Printer strobe
|
Strobe for data exchange (edge pulse)
|
CASRMT
|
Audio cassette remote
|
0: ON 1:OFF
|
CASWR
|
Audio cassette data
|
Write data, MIC
|
|
|
$FD01
|
R
|
Keyboard data low 8 bits
Bit |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
0
|
Name
|
Keyboard data bits 0~7
|
|
W
|
Printer output data
Bit |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
0
|
Name
|
Output data
|
|
|
$FD02
|
R
|
Audio cassette and printer
Bit |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
0
|
Name
|
CASRD
|
|
DET2
|
DTT1
|
PE
|
ACKNG
|
ERROR
|
BUSY
|
CASRD
|
Cassette data read, SPK
|
|
DET2
|
Printer DET 2
|
(unused)
|
DTT1
|
Printer DTT 1
|
(unused)
|
PE
|
Printer Paper Empty
|
0: Normal 1: No paper用紙なし
|
ACKNG
|
Acknowledge
|
Triggered by reading (?)
|
ERROR
|
Printer Error
|
0: Error 1: Normal
|
BUSY
|
Printer Busy
|
0: Ready 1: Busy
|
|
W
|
Interrupt mask
Bit |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
0
|
Name
|
SYNDET
|
RXRDY
|
TXRDY
|
MFD
|
|
TIMER
|
PRINTER
|
KEY
|
SYNDET
|
RS-232 sync detect
|
0: Disable 1: Enable
|
RXRDY
|
RS-232 serial receive ready
|
TXRDY
|
RS-232 serial transmit ready
|
MFD
|
Mini-floppy disk
|
TIMER
|
Periodic timer (every 2.03ms)
|
PRINTER
|
Printer ready for next character
|
KEY
|
Keystroke received
|
|
|
$FD03
|
R
|
Interrupt flags
Bit |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
0
|
Name
|
|
EXT
|
TIMER
|
PRINTER
|
KEY
|
EXT
|
Expansion
|
0: Active 1: Inactive
|
TIMER
|
Periodic timer
|
PRINTER
|
Printer ready for next character
|
KEY
|
Keystroke received
|
|
W
|
Buzzer
Bit |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
0
|
Name
|
REPEAT
|
SINGLE
|
|
SPEAKER
|
REPEAT
|
Repeating buzzer
|
0: Off 1: On
|
SINGLE
|
One-shot buzzer
|
0: Off 1: On
|
SPEAKER
|
Output buzzer to speaker
|
0: Mute 1: Output
|
|