HSP3824 Datasheet, PDF (5/41 Pages) Harris Corporation – Direct Sequence Spread Spectrum Baseband Processor

HSP3824
Pin Description (Continued)
NAME
MD_RDY
PIN
TYPE I/O
34
O
RX_PE
33
I
ANTSEL
27
O
SD
25
I/O
SCLK
24
I
AS
23
I
R/W
8
I
CS
9
I
TEST 0-7
37, 38, 39,
O
40, 43, 44,
45, 46
TEST_CK
1
O
RESET
28
I
MCLK
30
I
I_OUT
48
O
Q_OUT
47
O
NOTE: Total of 48 pins; ALL pins are used.
DESCRIPTION
MD_RDY is an output signal to the network processor, indicating a data packet is
ready to be transferred to the processor. MD_RDY is an active high signal and it
envelopes the data transfer over the RXD serial bus. MD_RDY returns to its inactive
state when there is no more receiver data, when the programmable data length
counter reaches its value or when the link has been interrupted. MD_RDY remains
inactive during preamble synchronization.
When active, receiver is configured to be operational, otherwise receiver is in standby
mode. This is an active high input signal.
The antenna select signal changes state as the receiver switches from antenna to
antenna during the acquisition process in the antenna diversity mode.
SD is a serial bi-directional data bus which is used to transfer address and data to/from
the internal registers. The bit ordering of an 8-bit word is MSB first. The first 8 bits
during transfers indicate the register address immediately followed by 8 more bits
representing the data that needs to be written or read at that register.
SCLK is the clock for the SD serial bus.The data on SD is clocked at the rising edge.
SCLK is an input clock and it is asynchronous to the internal master clock (MCLK)The
maximum rate of this clock is 10MHz or the master clock frequency, whichever is
lower.
AS is an address strobe used to envelope the Address or the data on SD.
Logic 1 = envelopes the address bits.
Logic 0 = envelopes the data bits.
R/W is an input to the HSP3824 used to change the direction of the SD bus when
reading or writing data on the SD bus. R/W must be set up prior to the rising edge of
SCLK. A high level indicates read while a low level is a write.
CS is a Chip select for the device to activate the serial control port.The CS doesn’t
impact any of the other interface ports and signals, i.e. the TX or RX ports and
interface signals. This is an active low signal. When inactive SD, SCLK, AS and R/W
become “don’t care” signals.
This is a data port that can be programmed to bring out internal signals or data for
monitoring. This data includes: Correlator phase and magnitude, NCO frequency
offset estimate, and signal quality estimates. Some of the discrete signals available
include: Carrier Sense (CRS), which becomes active when initial PN acquisition has
been declared. Energy Detect (ED) which becomes active when the integrated RSSI
value exceeds the programmable threshold. Both ED and CRS are active high
signals.These bits are primarily reserved by the manufacturer for testing. A further
description of the test port is given at the appropriate section of this data sheet.
This is the clock that is used in conjunction with the data that is being output from the
test bus (TEST 0-7).
Master reset for device. When active TX and RX functions are disabled. If RESET is
kept low the HSP3824 goes into the power standby mode. RESET does not alter any
of the configuration register values nor it presets any of the registers into default
values. Device requires programming upon power-up. RESET must be inactive during
programming of the device.
Master Clock for device. The maximum frequency of this clock is 44MHz. This is used
internally to generate all other internal necessary clocks and is divided by 1, 2, 4, or 8
for the transceiver clocks.
TX Spread baseband I digital output data. Data is output at the programmed chip rate.
TX Spread baseband Q digital output data. Data is output at the programmed chip
rate.
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