Microsemi ZL70550, Руководство пользователя

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ZL70550 Application Development Kit (ADK) User’s Guide
Revisio n 1 18
Note: Before running a PER test, be sure to set the following to the desired settings:
- The LNA gain on the BASE550 board using a combination of the
lna_bias_trim[3:0] on the CCA & Cal tab and the LNA Setting on the Test tab.
- The RSSI threshold on the BASE550 board on the CCA & Cal tab.
- The PA power on the REMOTE550 board using the TX Pwr Setting on the
Test tab .
These three parameters can greatly affect the results of the PER test. The
PER test does not set these parameters when the test is run, as it assumes
that the user wants to adjust these numbers for the specific application.
The functions for the PER test are:
−
PER Setup: The fields in the PER Setup group allow the user to set up the PER
test.
- # Packets : This field defines how many packets the user wants to send. The
limit for the PER test is 1,000 packets.
- Payload (Bytes) : This field defines how many bytes of payload per packet.
The payload data is an incrementing pattern starting with 0x00.
- FEC : This checkbox determines whether FEC is enabled for the packet
transaction.
- CSMA : This checkbox determines whether the REMOTE550 performs a
CSMA before transmitting the packet to the BASE550.
- Z-Star: This checkbox determines whether the BASE550 sends an
acknowledgement packet back to the REMOTE550. If this box is not
checked, no acknowledgment packet is sent.
−
Data Rate: The user can set the data rate at which the PER test is to run. The
selection is either 200 kbit/s, 100 kbit/s, or 50 kbit/s.
−
PER Status: This group displays the results from the PER test. The read-only
result fields are:
- Pkts Transmitted : This field displays the total number of packets that were
transmitted. If the transmitter has to retransmit packets while in Z-Star mode,
this field is greater than the number of packets defined in the
PER Setup
group.
- TX Pkt Retry : This field displays how many packets were retransmitted
during the PER test.
- TX Pkt Drop : This field displays how many packets were dropped on the
transmitting side for the PER test.
- CSMA Retries : If CSMA is enabled on the transmitter, this field displays how
many CSMA retries there were during the PER test.
- CSMA Fails : If CSMA is enabled, this field displays how many CSMA
failures there were for the PER test. A CSMA failure may occur if there is an
unwanted signal transmitting on the same operating frequency on which the
PER test is being run.
Note: The CSMA RSSI value on the CCA & Cal tab has an effect on the CSMA
Retries and CSMA Fails results. If the CSMA RSSI value is set too low, the
CSMA fails because the transmitter thinks there is a signal above this
threshold and therefore does not transmit the packet. A good rule of thumb is
to set the CSMA and RX RSSI threshold values to four counts above the noise