Little Board™/486e Technical Manual
2–68
Table 2–48. AT Expansion Bus Connector, C0-C19 (P2)
Pin Signal
Name Function In/Out Current PU/PD/S *
C0
C1
C2
C3
C4
C5
C6
C7
C8
C9
C10
C11
C12
C13
C14
C15
C16
C17
C18
C19
GND
SBHE
LA23
LA22
LA21
LA20
LA19
LA18
LA17
MEMR*
MEMW*
SD8
SD9
SD10
SD11
SD12
SD13
SD14
SD15
Key
Ground
Bus High Enable
Address bit 23
Address bit 22
Address bit 21
Address bit 20
Address bit 19
Address bit 18
Address bit 17
Memory Read
Memory Write
Data Bit 8
Data Bit 9
Data Bit 10
Data Bit 11
Data Bit 12
Data Bit 13
Data Bit 14
Data Bit 15
Key Pin
N/A
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
N/A
N/A
4 mA
12 mA
12 mA
12 mA
12 mA
12 mA
12 mA
12 mA
4 mA
4 mA
4 mA
4 mA
4 mA
4 mA
4 mA
4 mA
4 mA
4 mA
N/A
27K PU
27K PU
4.7K PU
4.7K PU
4.7K PU
4.7K PU
4.7K PU
4.7K PU
4.7K PU
4.7K PU
* PU = pull up; PD = pull down; S = resistanc e i n seri es. All v alues in ohm s.