
____________________________________________________ DS34T101, DS34T102, DS34T104, DS34T108
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PIN DESCRIPTION
H_WR_BE2_N /
SPI_SEL_N
I
H_WR_BE2_N: Host Write Enable Byte 2 (Active Low)
In 32-bit parallel interface mode during a write access this pin specifies whether or
not byte 2
(H_D[15:8]) should be written to the device. In 16-bit parallel interface
mode this pin is ignored and should be pulled high or low.
0 = write byte 2
1 = don’t write byte 2
SPI_SEL: SPI Chip Select (Active Low)
In SPI interface mode this pin must be asserted (low) to read or write internal
registers.
H_WR_BE3_N /
SPI_CI
I
H_WR_BE3_N: Host Write Enable Byte 3 (Active Low)
In 32-bit parallel interface mode during a write access this pin specifies whether or
not byte 3
(H_D[15:8]) should be written to the device. In 16-bit parallel interface
mode this pin is ignored and should be pulled high or low.
0 = write byte 3
1 = don’t write byte 3
SPI_CI: SPI Clock Invert
In SPI interface mode this pin specifies the polarity of the
SPI_CLK pin. See the
0 =
SPI_CLK is normally low and pulses high (leading edge is rising edge)
1 =
SPI_CLK is normally high and pulses low (leading edge is falling edge)
H_READY_N
O
8mA
Host Ready Output (Active Low)
In parallel interface mode the device pulls this pin low during a read or write
access to signal that the device is ready for the access to be completed. The host
processor should not pull
H_CS_N high (inactive) to complete the access until the device
has pulled H_READY_N low.
This pin requires the use of an external pull-up resistor. The device actively drives
this pin high before allowing it to go high-impedance. See
Figure 14-9.H_INT[1:0]
O
8mA
Host Interrupt Outputs (Active Low)
H_INT[0] indicates interrupt requests from the TDMoP block. H_INT[1] indicates
interrupt requests from the LIU, framer and BERT. Optionally, the H_INT[1] signal
can be forced inactive at the H_INT[1] pin and internally ORed into the H_INT[0]
signal by setting
GCR1.IPOR=1. This allows H_INT[0] to indicate interrupt
requests from any and all sources in the device. When
GCR1.IPI0=1, H_INT[0] is
forced high (inactive). When
GCR1.IPI1=1, H_INT[1] is forced high (inactive). See