
DS26518 8-Port T1/E1/J1 Transceiver
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NAME
PIN
TYPE
FUNCTION
MICROPROCESSOR INTERFACE
A12
C8
A11
A8
A10
B8
A9
F8
A8
B9
A7
A9
A6
C9
A5
D9
A4
E9
A3
F9
A2
B10
A1
A10
A0
C10
Input
Address [12:0]. This bus selects a specific register in the DS26518 during
read/write access. A12 is the MSB and A0 is the LSB.
D7/SPI_CPOL
T9
Input/
Output
Data 7/SPI Interface Clock Polarity
D7: Bit 7 of the 8-bit data bus used to input data during register writes and data
outputs during register reads. Not driven when
CSB = 1.
SPI_CPOL: This signal selects the clock polarity when SPI_SEL = 1. See Section
9.1.2 for detailed timing and functionality information. Default setting is low.
D6/SPI_CPHA
N9
Input/
Output
Data 6/SPI Interface Clock Phase
D6: Bit 6 of the 8-bit data bus used to input data during register writes and data
outputs during register reads. Not driven when
CSB = 1.
SPI_CPHA: This signal selects the clock phase when SPI_SEL = 1. See Section
9.1.2 for detailed timing and functionality information. Default setting is low.
D5/SPI_SWAP
M9
Input/
Output
Data 5/SPI Bit Order Swap
D5: Bit 5 of the 8-bit data bus used to input data during register writes and data
outputs during register reads. Not driven when
CSB = 1.
SPI_SWAP: This signal is active when SPI_SEL = 1. The address and data bit
order is swapped when SPI_SWAP is high. The R/W and B bit positions are
never changed in the control word.
0 = LSB is transmitted and received first.
1 = MSB is transmitted and received first.
D4
R8
Input/
Output
Data 4. Bit 4 of the 8-bit data bus used to input data during register writes and
data outputs during register reads. Not driven when
CSB = 1.
D3
T8
Input/
Output
Data 3. Bit 3 of the 8-bit data bus used to input data during register writes and
data outputs during register reads. Not driven when
CSB = 1.
D2/SPI_SCLK
P8
Input/
Output
Data 2/SPI Serial Interface Clock
D2: Bit 2 of the 8-bit data bus used to input data during register writes and data
outputs during register reads. Not driven when
CSB = 1.
SPI_SCLK: SPI Serial Clock Input when SPI_SEL = 1.
D1/SPI_MOSI
L9
Input/
Ouput
Data 1/SPI Serial Interface Data Master Out-Slave In
D1: Bit 1 of the 8-bit data bus used to input data during register writes, and data
outputs during register reads. Not driven when
CSB = 1.
SPI_MOSI: SPI Serial Data Input (Master Out-Slave In) when SPI_SEL = 1.
D0/SPI_MISO
N8
Input/
Output
Data 0/SPI Serial Interface Data Master In-Slave Out
D0: Bit 0 of the 8-bit data bus used to input data during register writes and data
outputs during register reads. Not driven when
CSB = 1.
SPI_MISO: SPI Serial Data Output (Master In-Slave Out) when SPI_SEL = 1.
CSB
T7
Input
Chip-Select Bar. This active-low signal is used to qualify register read/write
accesses. The
RDB/DSB and WRB/ RWB signals are qualified with CSB.
RDB/
DSB
M8
Input
Read Bar/Data-Strobe Bar. This active-low signal along with
CSB qualifies read
access to one of the DS26518 registers. The DS26518 drives the data bus with
the contents of the addressed register, in Intel bus mode, while
RDB and CSB are
low or, in Motorola bus mode, while
DSB and CSB are low and RWB is high.