Maxim Integrated DS21Q55 User Manual
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Signal Name:
MUX
Signal Description:
Bus Operation
Signal Type:
Input
Set low to select nonmultiplexed bus operation. Set high to select multiplexed bus operation.
Signal Name:
D0/AD0 to D7/AD7
Signal Description:
Data Bus [D0 to D7] or Address/Data Bus
Signal Type:
Input/Output
In nonmultiplexed bus operation (MUX = 0), it serves as the data bus. In multiplexed bus operation (MUX = 1), it serves as an
8-bit, multiplexed address/data bus.
Signal Name:
A0 to A6
Signal Description:
Address Bus
Signal Type:
Input
In nonmultiplexed bus operation (MUX = 0), it serves as the address bus. In multiplexed bus operation (MUX = 1), these pins
are not used and should be tied low.
Signal Name:
BTS
Signal Description:
Bus Type Select
Signal Type:
Input
Strap high to select Motorola bus timing; strap low to select Intel bus timing. This pin controls the function of the RD*(DS*),
A7/ALE(AS), and WR*(R/W*) pins. If BTS = 1, then these pins assume the function listed in parenthesis ().
Signal Name:
RD*(DS*)
Signal Description:
Read Input-Data Strobe
Signal Type:
Input
RD* and DS* are active-low signals. DS active HIGH when MUX = 0. See bus timing diagrams.
Signal Name:
CS1*
Signal Description:
Chip Select for transceiver #1
Signal Type:
Input
Must be low to read or write to transceiver #1 of the device. CS1* is an active-low signal.
Signal Name:
CS2*
Signal Description:
Chip Select for transceiver #2
Signal Type:
Input
Must be low to read or write to transceiver #2 of the device. CS2* is an active-low signal.
Signal Name:
CS3*
Signal Description:
Chip Select for transceiver #3
Signal Type:
Input
Must be low to read or write to transceiver #3 of the device. CS3* is an active-low signal.
Signal Name:
CS4*
Signal Description:
Chip Select for transceiver #4
Signal Type:
Input
Must be low to read or write to transceiver #4 of the device. CS4* is an active-low signal.