Spectravideo SVI 318 Service – Technical Manual page 69

S V I -3 1 8 AND S V I -3 2 8 I / 0 PORT LOCAT I ON
I / 0 PORT R /W
l OH w
l l H
w
R
1 2 H
R
20H
w
w
2 1 H
w
w
2 2 H w
2 3 H w
2 4H w
R
2 5 H
R
2 6 H
R
2 8H
w
w
2 9 H w
w
2AH
w
2 BH w
2 C H
w
R
2 DH
R
3 0 H
w
R/W
3 1 H
R/W
3 2 H
R /W
3 3 H
R
3 4 H
w
3 8 H
w
SOH w
S l H w
58H
w
80H w
8 1 H
w
8 4H R
R
8 5H
8 8 H
w
8 C H
w
90 H
R
96H w
9 7 H
w
R
9 8H
R
9 9 H
DESCR I PT I ON
WR I T E DATA P ORT
DATA S TROBE
STATUS ( B IT 0 =
" 0"
RECE I VER BUFFER REG I S T E R
DI V I S OR LATCH ( LEAST S I GN I F I CAN T )
TRAN S M I TTER HO LD ING BUFFER REG .
D I V I S OR ( MOST S I GN I F I CAN T )
LATCH
I N TERRUPT ENABLE REG I S TE R
INT ERRUPT I DENT I F I CAT ION RE G I STER
L I N E CONTROL REG I S T ER
READ MO DEM CONTROL REG I STER
L I N E S TATU S REGI STER
READ MODEM STATUS REG I STER
RECE I VER BUFFER REG I S TER
( LEAST S I GN I F I CANT )
D I V I S OR BUFFER REG I S T E R
TRANSMITTER HOLDING BUFFE R REG I STER
D I V I S OR LATCH ( MOST S I GN I F ICANT )
INTERRUPT ENABLE REG I S TER
I NTERRUPT IDEN T I F I CAT I ON REGISTER
LINE CONTROL REG ISTER
MOD EM CONTRO L REG ISTER
LINE STATU S REG I STER
STATU S REG I S T E R
FD- 1 7 9 3
FD- 1 7 93 COMMAND REG I STER
FD- 1 793 TRACK REG I S T E R
FD- 1 7 93 S ECTOR REG ISTER
FD- 1 7 93 DATA REG I S TER
READ INTRQ AN D DRQ 0 / P P I NS
D I S K SE LECT REGI STER
( B I T 0 = " 0" TO SELECT DISK
B I T 1 = "0" TO SELE CT D I S K
DEN S I TY SEL ECT REG ISTER
( B I T 0 = " 0 " FOR DOU BLE DEN .
B I T 0 = " 1 " FOR S I NGLE DEN . )
ADDRES S REG I S TER SELECT
CRT CONTRO LLER REG I STER ( RO-Rl 7 )
CRT BANK CONTROL
( = OFFH BANK ON , = OOH BANK O FF )
TM S-99 1 8 A WRITE MODE=O
TMS-99 18A WR ITE MODE = 1
TM S-99 1 8 A READ MODE=O
TMS- 99 1 8A READ MODE = l
AY- 3-8 9 1 0 LATCH ADDRE S S
AY-3 -8 9 1 0 WRITE
AY-3 -89 1 0 READ
WR ITE 8 2 55 PORT C
WR I T E 8 2 5 5 CONTROL WORD REG ISTER
READ 8 2 5 5 P ORT A
READ 8 2 5 5 P ORT B
4 . 36
FOR READY )
1
2 )
REMARK
PR INTER
P R I NTER
PR I NTER
MODEM
MODEH
MODEH
MODEM
MODEM
MODEM
MODEM
MODEM
MODEM
MODEM
RS- 2 3 2
R S - 2 3 2
RS- 2 3 2
RS- 2 3 2
RS- 2 3 2
RS- 2 3 2
RS- 2 3 2
RS- 2 3 2
RS- 2 3 2
FLOPPY D I SK
FLOPPY D I S K
FLOPPY D I SK
FLOPPY D I SK
FLOPPY D I SK
FLOPPY D I SK
FLOPPY D I SK
FLO PPY D I S K
80-COLUMN CARD
80-COLUMN CARD
SO-COLUMN CARD
VDP
VDP
VDP
VDP
P S G
P S G
P S G
PP I
P P I
P P I
P P I