Rainbow Electronics DS21458 - Manual (Page 25)

DS21455/DS21458 Quad T1/E1/J1 Transceivers
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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:
AD0 to 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:
A8 and A9 (DS21458 Only)
Signal Description: Address Bus
Signal Type: Input
Upper address pins for nonmultiplexed (MUX = 0), and multiplexed (MUX = 1) bus operation,.
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),
ALE (AS), and WR (R/W) pins. If BTS = 1, then these pins assume the function listed in parentheses ().
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 the bus timing diagrams.
Signal Name:
CS1 (DS21455 Only)
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 (DS21455 Only)
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 (DS21455 Only)
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 (DS21455 Only)
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.