
AMD
P R E L I M I N A R Y
38
Am79C930
Pin 101: SDCLK
The SDCLK pin may be configured for input or output
operation. The output drive may be programmed for reg-
ister-driven or auto-pulse generation. The auto-pulse
may be programmed for either active low or active high
operation. SDCLK pin configuration is accomplished ac-
cording to the following table:
Note that a read of the SDC bit (TIR2[2]) will always
give the current SDCLK pin value, regardless of pin
configuration setting.
SDCLKEN
TCR13[4]
0
1
1
1
1
SDCP
TIR2[3]
X
0
1
0
1
SDC
TIR2[2]
X
0
0
1
1
SDCLK Pin
Direction
I
O
O
O
O
SDCLK Pin
Value
NA
LOW
HIGH active pulse
HIGH
LOW active pulse
reset default condition
(when write to TIR2 occurs)
(when write to TIR2 occurs)
Pin 102: SDDATA
The SDDATA pin may be configured for input or output
operation. SDDATA pin configuration is accomplished
according to the following table:
Note that a read of the SDD bit (TIR2[0]) will always
give the current SDDATA pin value, regardless of pin
configuration setting.
SDDT
TIR2[1]
0
0
1
SDD
TIR2[0]
0
1
X
SDDATA Pin
Direction
O
O
I
SDDATA Pin
Value
LOW
HIGH
NA
reset default condition
Pin 103:
SDSEL3
The
SDSEL
[
3
] pin may be configured for input or output
operation according to the following table:
Note that a read of the SDS[3] bit (TIR2[6]) will always
give the current
SDSEL
[
3
] pin value without inversion,
regardless of pin configuration setting.
SDSEL3
EN
TCR13[3]
0
1
1
SDS[
3
]
TIR2[6]
X
0
1
SDSEL
[
3
]
Pin Direction
I
O
O
SDSEL
[
3
]
Pin Value
NA
HIGH
LOW
reset default condition
Pin 105:
SDSEL2
The
SDSEL
[
2
] pin may be configured for input or output
operation according to the following table:
Note that a read of the SDS[2] bit (TIR2[5]) will always
give the current
SDSEL
[
2
] pin value without inversion,
regardless of pin configuration setting.
SDSEL2
EN
TCR13[2]
0
1
1
SDS[
2
]
TIR2[5]
X
0
1
SDSEL
[
2
]
Pin Direction
I
O
O
SDSEL
[
2
]
Pin Value
NA
HIGH
LOW
reset default condition
Pin 107:
SDSEL1
The
SDSEL
[
1
] pin may be configured for input or output
operation according to the following table:
Note that a read of the SDS[1] bit (TIR2[4]) will always
give the current
SDSEL
[
1
] pin value without inversion,
regardless of pin configuration setting.
SDSEL1
EN
TCR13[1]
0
1
1
SDS[1]
TIR2[4]
X
0
1
SDSEL
[1]
Pin Direction
I
O
O
SDSEL
[1]
Pin Value
NA
HIGH
LOW
reset default condition