
42
MB86604L
s LIST OF REGISTERS
1.
BASIC Control Registers (for write)
2.
BASIC Control Registers (for read)
Note: X indicates data is undefined. (0 or 1).
Address
Register name
Bit assignment
Hex. A4 A3 A2 A1 A0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
00
0
0 Output data register (first)
DO7
DO6
DO5
DO4
DO3
DO2
DO1
DO0
01
00
001 Output data register (second)
DO15 DO14 DO13 DO12 DO11 DO10 DO9
DO8
02
0
1
0 Direct control register
DC7
0
DO4
0000
03
0
1
1 (Reserved)
0
0000000
04
0
1
0
0 SEL/RESEL ID register
SI7
0000
SI2
SI1
SI0
05
0
1
0
1 Command register
CM7
CM6
CM5
CM4
CM3
CM2
CM1
CM0
06
0
1
0 Data block register (MSB)
BL15 BL14 BL13 BL12 BL11 BL10
BL9
BL8
07
0
1
1 Data block register (LSB)
BL7
BL6
BL5
BL4
BL3
BL2
BL1
BL0
08
0
1
0
0 Data byte register (MSB)
BY23 BY22 BY21 BY20 BY19 BY18 BY17 BY16
09
0
1
0
1 Data byte register
BY15 BY14 BY13 BY12 BY11 BY10
BY9
BY8
0A
01
010
Data byte register (LSB)
BY7
BY6
BY5
BY4
BY3
BY2
BY1
BY0
MC byte register
0B
0
1
0
1
1 Diagnostic control register
DG7
DG6
DG5
0
DG3
DG2
DG1
DG0
0C
0
1
0
0 Transfer mode register
TM7
0000000
0D
0
1
0
1 Transfer period register
0
TP4
TP3
TP2
TP1
TP0
0E
0
1
0 Transfer offset register
0
TO4
TO3
TO2
TO1
TO0
0F
0
1
1 Window address register
WA7
WA6
0
WA3
WA2
WA1
WA0
Address
Register name
Bit assignment
Hex. A4 A3 A2 A1 A0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
00
0
0 Input data register (first)
DI7
DI6
DI5
DI4
DI3
DI2
DI1
DI0
01
0
1 Input data register (second)
DI15
DI14
DI13
DI12
DI11
DI10
DI9
DI8
02
0
1
0 SPC status register
SS7
SS6
SS5
SS4
X
SS2
SS1
SS0
03
0
1
1 Nexus status register
NS7
NS6
NS5
X
NS2
NS1
NS0
04
0
1
0
0 Interrupt status register
IS7
IS6
IS5
IS4
IS3
IS2
IS1
IS0
05
0
1
0
1 Command step register
CS7
CS6
CS5
CS4
CS3
CS2
CS1
CS0
06
0
1
0 Data block register (MSB)
BL15 BL14 BL13 BL12 BL11 BL10
BL9
BL8
07
0
1
1 Data block register (LSB)
BL7
BL6
BL5
BL4
BL3
BL2
BL1
BL0
08
0
1
0
0 Data byte register (MSB)
BY23 BY22 BY21 BY20 BY19 BY18 BY17 BY16
09
0
1
0
1 Data byte register
BY15 BY14 BY13 BY12 BY11 BY10
BY9
BY8
0A
01
010
Data byte register (LSB)
BY7
BY6
BY5
BY4
BY3
BY2
BY1
BY0
MC byte register
0B
01
011 SCSI control signal status register
SC7
SC6
SC5
SC4
SC3
SC2
SC1
SC0
0C
0
1
0
0 Transfer mode register
TM7
XXX
XXXX
0D
0
1
0
1 Transfer period register
X
TP4
TP3
TP2
TP1
TP0
0E
0
1
0 Transfer offset register
X
TO4
TO3
TO2
TO1
TO0
0F
0
1
1 Modified byte register
X
MB5
BM4
MB3
MB2
MB1
MB0