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Line 1: − + + + + + − The VOTER is the original through-hole board designed by Jim Dixon for this application. It is open-source, and the relevant Gerber files and BoM to build it are available. + + + − The [http://www.micro-node.com/thin-m1.shtml Micro-Node Radio Thin Client Module (RTCM)] is the commercial version of the VOTER. It uses surface mount parts (SMT), but is functionally equivalent to the original VOTER. + − + − − In general, the two terms (RTCM/VOTER) are used interchangeably, as they operate the same, and use the same firmware (mostly, see below). − − − This page will highlight some of the operational concerns, quirks, bugs, and other items of interest that relate to these interfaces. Much of the information has been gleaned off the AllStar mail list, comes from personal experience, or comes from notes in the firmware source code. − Line 27:
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no edit summary
The Micro-Node RTCM and VOTER interfaces are typically used with AllStar in voting/simulcast applications. They MAY be used for ANY repeater interface application, through the chan/voter channel driver.
[[Category:How to]]
[[Category:Node Configuration]]
[[Category:Hardware]]
The Radio Thin Client Module (RTCM) is commercially available hardware for interfacing radios to an PTTLink computer.
The Micro-Node RTCM and VOTER interfaces are typically used with PTTLink in voting/simulcast applications. They MAY be used for ANY repeater interface application, through the chan_voter channel driver. The VOTER is the original through-hole board designed by Jim Dixon for this application. It is open-source, and the relevant Gerber files and BoM to build it are available. The [http://www.micro-node.com/thin-m1.shtml Micro-Node Radio Thin Client Module (RTCM)] is the commercial version of the VOTER. It uses surface mount parts (SMT), but is functionally equivalent to the original VOTER. In general, the two terms (RTCM/VOTER) are used interchangeably, as they operate the same, and use the same firmware (mostly, see below).
This page will highlight some of the operational concerns, quirks, bugs, and other items of interest that relate to these interfaces. Much of the information has been gleaned off the PTTLink mail list, comes from personal experience, or comes from notes in the firmware source code.
=Testing=
RTCM's come preconfigured to login to [http://voter-demo-pttlink.org voter-demo-pttlink.org] for out of the box testing.
=Factory Reset=
A factory reset can be performed by setting SW 1 down and then applying power to the RTCM. Wait for the green LED to stop blinking, power off and set SW 1 back up.
=Firmware=
=Firmware=
The current bootloader (.cof file) is available here: https://github.com/AllStarLink/voter/tree/master/voter-bootloader (the -smt file is for the RTCM). It needs to be loaded with a PICKit programmer.
The current bootloader (.cof file) is available here: https://github.com/pttLink/voter/tree/master/voter-bootloader (the -smt file is for the RTCM). It needs to be loaded with a PICKit programmer.
Current firmware (.cry file) is available here: https://github.com/AllStarLink/voter/tree/master/board-firmware . They are loaded with the EBLEX C30 Programmer.
Current firmware (.cry file) is available here: https://github.com/pttLink/voter/tree/master/board-firmware . They are loaded with the EBLEX C30 Programmer.
==Compiling Environment==
==Compiling Environment==
If you look in the [https://github.com/AllStarLink/voter/blob/master/votersystem.pdf votersystem.pdf], you will find a procedure to modify and load the bootloader in to the dsPIC of a VOTER board.
If you look in the [https://github.com/PTTLink/voter/blob/master/votersystem.pdf votersystem.pdf], you will find a procedure to modify and load the bootloader in to the dsPIC of a VOTER board.
Download MPLAB IDE 32-bit Windows v8.66:
Download MPLAB IDE 32-bit Windows v8.66:
:http://ww1.microchip.com/downloads/en/DeviceDoc/MPLAB_IDE_v8_66.zip
:http://ww1.microchip.com/downloads/en/DeviceDoc/MPLAB_IDE_v8_66.zip
:http://dvswitch.org/files/AllStarLink/Voter/MPLAB_IDE_v8_66.zip
:http://dvswitch.org/files/pttLink/Voter/MPLAB_IDE_v8_66.zip
Download MPLAB C Compiler for PIC24 and dsPIC DSCs v3.31 '''NOT v.3.25''':
Download MPLAB C Compiler for PIC24 and dsPIC DSCs v3.31 '''NOT v.3.25''':
:http://ww1.microchip.com/downloads/en/DeviceDoc/mplabc30-v3_31-windows-installer.exe
:http://ww1.microchip.com/downloads/en/DeviceDoc/mplabc30-v3_31-windows-installer.exe
:http://dvswitch.org/files/AllStarLink/Voter/mplabc30-v3_31-windows-installer.exe
:http://dvswitch.org/files/pttLink/Voter/mplabc30-v3_31-windows-installer.exe
*Select Legacy Directory Name
*Select Legacy Directory Name
*'''Select Lite Compiler'''
*'''Select Lite Compiler'''
*Go to: https://github.com/AllStarLink
*Go to: https://github.com/pttLink
*Follow the links to: voter --> Clone or Download --> Download Zip. That will get you voter-master.zip which is a download of the whole VOTER tree from GitHub.
*Follow the links to: voter --> Clone or Download --> Download Zip. That will get you voter-master.zip which is a download of the whole VOTER tree from GitHub.
*Extract it somewhere (ie. in the XP Mode Virtual PC)
*Extract it somewhere (ie. in the XP Mode Virtual PC)
Pre-compiled firmware versions including this option are available on [https://github.com/AllStarLink/voter/tree/master/board-firmware GitHub]. See above on how it is enabled/compiled, if you are rolling your own firmware modifications.
Pre-compiled firmware versions including this option are available on [https://github.com/pttLink/voter/tree/master/board-firmware GitHub]. See above on how it is enabled/compiled, if you are rolling your own firmware modifications.
You may also want to consider the following changes in /etc/asterisk/voter.conf:
You may also want to consider the following changes in [[Voter.conf|/etc/asterisk/voter.conf]]:
<pre>
<pre>
;Comment out:
;Comment out:
</pre>
</pre>
=Squelch Issues=
*If anyone is off frequency a little bit, that will make the voice talk off worse. Double check that the repeater and the users are all on frequency.
*If anyone is off frequency a little bit, that will make the voice talk off worse. Double check that the repeater and the users are all on frequency.
*Don't use narrow bandwidth on the repeater receiver.
*Don't use narrow bandwidth on the repeater receiver.
*Make sure that the discriminator audio is not rolled off even a little bit at the high end. There should not be resistors in series or capacitors to ground between the discriminator chip output pin and the voter board input, for best results.
*Make sure that the discriminator audio is not rolled off even a little bit at the high end. There should not be resistors in series or capacitors to ground between the discriminator chip output pin and the voter board input, for best results.
==Motorola Quantar==
Some things to consider:
*Install JP1 on the Quantar's RTCM. The squelch should calibrate at around 4 blinks rather than the 12 blinks or so without JP1.
*Be sure you've done the diode and squelch calibration with the actual attached radio (no antenna).
*The Quantar firmware should be 20.14.48 as later versions have better noise output.
*Try the "Chuck Squelch" RTCM version.
*Each RTCM should have 3 to 5 turns past threshold to prevent the squelch form being too loose. Somewhere around the 350 level seems about right. Chuck Squelch seems to need fewer turns but YMMV.
*Don't "and" CTCSS with squelch. That may override the RTCM's squelch detection. Compare with CTCSS on and off to see effect if any.
Also check the [[Quantar_RTCM|Quantar RTCM]] page for detailed interfacing and configuration information.
=RTCM/VOTER LED's=
=RTCM/VOTER LED's=
Enter Selection (1-9,99,c,x,q,r) :
Enter Selection (1-9,99,c,x,q,r) :
</pre>
</pre>
==Status Menu==
This is what a typical Status Menu looks like:
<pre>
S/W Version: 1.51 BEW 08/07/2017 Chuck
System Uptime: 19569.3 Secs
IP Address: 172.16.16.191
Netmask: 255.255.255.0
Gateway: 172.16.16.254
Primary DNS: 172.16.16.254
Secondary DNS: 0.0.0.0
DHCP: 0
VOTER Server IP: 172.16.16.164
VOTER Server UDP Port: 667
OUR UDP Port: 667
GPS Lock: 1
Connected: 1
COR: 0
EXT CTCSS IN: 0
PTT: 0
RSSI: 0
Current Samples / Sec.: 8000
Current Peak Audio Level: 58112
Squelch Noise Gain Value: 45, Diode Cal. Value: 56, SQL pot 621
Current Time: Mon Dec 07, 2020 02:15:25.120
Last Rx Pkt System time: 12/07/2020 02:05:32.340, diff: 592780 msec
Last Rx Pkt Timestamp time: 12/07/2020 02:05:32.340, diff: 0 msec
Last Rx Pkt index: 320, inbounds: 1
Press The Any Key (Enter) To Continue
</pre>
Something to note about the "Last Rx Pkt" status. This is the last received packet '''from the network''', not over the air. As such, on your satellite voter receivers that are receive-only, you will likely see something like:
<pre>
Last Rx Pkt System time: <System Time Not Set>, diff: 990080296 msec
Last Rx Pkt Timestamp time: <System Time Not Set>, diff: 0 msec
Last Rx Pkt index: 0, inbounds: 0
</pre>
The Last Rx Pkt System Time is the last time a packet was sent to this device to be transmitted (diff: is how many msec ago that was).
The Last Rx Pkt Timestamp Time is what the timestamp embedded in that last TX packet was, and the diff: is the difference between the packet timestamp, and the system time.
=Configuration Options=
=Configuration Options=
Just want ToS turned on, set debug to 16.
Just want ToS turned on, set debug to 16.
=Un-documented Menus/Features=
=Un-documented Menus/Features=
*Menu 111 - show the "hidden" option values (normally they should all be 0).
*Menu 111 - show the "hidden" option values (normally they should all be 0).
*Menu 11780 - set the "Elkes" value. Developed for Pete Elkes, this is for solar type sites. It shuts off the Tx after a period of no Rx activity.
*Menu 11780 - set the "Elkes" value. Developed for Pete Elke WI6H, this is for solar type sites. It shuts off the Tx after a period of no Rx activity.
*Menu 1103 - set the "Glaser" timer value? No idea what this does.
*Menu 1103 - set the "Glaser" timer value? No idea what this does.
*Menu 1170 - set "Sawyer Mode". Developed for Tim Sawyer use on Yaesu VXR5000 repeater. It modifies de-ephasis behavior when on/off line.
*Menu 1170 - set "Sawyer Mode". Developed for Tim Sawyer use on Yaesu VXR5000 repeater. Only applicable in OFFLINE mode. Disabled (default) when 0. When set to 1, it forces the PL filter OFF (bypassed) when in OFFLINE mode (not connected to the host), regardless of the state that it normally would be configured in voter.conf. Normally, the PL filter is IN during OFFLINE mode. That should effectively allow you to configure true pass-through (no PL filter or de-emphasis) audio through the device, if you set the rest of the options correctly.
=Audio=
=Audio=
Optionally, if you are using the built-in "offline repeat" functions, fail the connection to the host Asterisk server, and make sure your repeat audio performs the same as above.
Optionally, if you are using the built-in "offline repeat" functions, fail the connection to the host Asterisk server, and make sure your repeat audio performs the same as above.
==== Resolution issues when setting levels using built VOTER boards ====
Sometimes, depending on what radio is being used getting a good enough resolution with R61 when setting levels is a problem. You move a small amount on the pot and it jumps several hundred KHz of deviation. Inserting a 4:1 voltage divider between the VOTER board and transmitter helps with this. Something such as a 1K and 330 ohm resistor will work. This allows for much finer adjustment on the transmit audio (R61).
==Crappy Transmit Audio==
==Crappy Transmit Audio==
Just enable and set the level to 0. You'll thank me later.
Just enable and set the level to 0. You'll thank me later.
== Pulse Noise on Transmit Audio ==
It has been noticed sometimes on built VOTER boards that it has low level DAC noise which sometimes is apparent as a pulsing noise on the audio output. Adding a 4:1 voltage divider inline between the transmitter and VOTER board helps reduce or eliminate this as described above in Level setting.
=GPS=
=GPS=
The firmware is specifically written to talk to Trimble Thunderbolt receivers using Trimble's TSIP binary data interface, however, other Trimbles GPS receivers that talk TSIP are generally compatible.
The firmware is specifically written to talk to Trimble Thunderbolt receivers using Trimble's TSIP binary data interface, however, other Trimbles GPS receivers that talk TSIP are generally compatible.
==RTCM GPS Connections==
There are some quirks specific to the RTCM that are not well documented.
The GPS connections for the RTCM are on the DB15 connector. Note that the labels for GTX and GRX are misleading. GTX is the data '''FROM''' the GPS '''TO''' the RTCM (GPS TX/RTCM RX). GRX is data from the RTCM to the GPS, but that is currently not used, so it does not need to be connected.
PPS is obvious, that is your PPS signal from your GPS.
Also note, inside the RTCM, there are jumpers to set for TTL or RS-232 data, depending on the type of GPS you are connecting. Set them accordingly. The RS-232 setting loops the data through a MAX3232 converter on the board.
You will still need to set the data and PPS polarity, and baud rate in the configuration menus to get everything to work.
$GPRMC
$GPRMC
</pre>
</pre>
==TSIP Packets==
If you are using a Trimble GPS that speaks TSIP, it needs to automatically send out the 0x8F-AB and 0x8F-AC timing packets. Such devices include the Thunderbolt, Resolution T, etc.
It is not unusual for it to take up to 20 mins to get a GPS lock LED (ie. using a Trimble Thunderbolt) after any reboot.
It is not unusual for it to take up to 20 mins to get a GPS lock LED (ie. using a Trimble Thunderbolt) after any reboot. With the Trimble GPS', that is because it is waiting to complete the download of the almanac, and clear the status flags.
I found the debug setting of 32 useful in the RTCM, you can see a hex output of the GPS status.
I found the debug setting of 32 useful in the RTCM, you can see a hex output of the GPS status.
</pre>
</pre>
That has also been observed when trying to use a cheap "patch" antenna in a high RF site (lots of TV/FM transmitters nearby). Switching to a "proper" (commercial) GPS antenna that actually has filtering in it resolved the issue.
We have added a brute-force fix starting in RTCM/VOTER firmware >=1.51. This fix adds 619315200 seconds (1024 weeks) to the time reported by the GPS. It fixes the Thunderbolts, we have not done extensive testing to see how it affects other TSIP receivers.
We have added a brute-force fix starting in RTCM/VOTER firmware >=1.51. This fix adds 619315200 seconds (1024 weeks) to the time reported by the GPS. It fixes the Thunderbolts, it breaks other TSIP receivers (Resolution T). A better fix is being tested.
===Garmin===
===Garmin===
The VOTER is designed to accept both 3.3V or 5V signals, and ''should'' work fine.
The VOTER is designed to accept both 3.3V or 5V signals, and ''should'' work fine.
* Some of the Garmin GPS's come with 4800 baud set as default. If you are getting a "Warning: GPS Data time period elapsed" error on your RTCM, change both the GPS and RTCM to use 9600 baud. To do this, interface the GPS to a DB9 connector as per page 8 of the [http://wiki.pttlink.org/w/images/4/41/GPS_18x_Tech_Specs.pdf manual] (remembering to ONLY use 5V as the power source *facepalm*). Once done, download, extract and open [http://www8.garmin.com/support/download_details.jsp?id=4053 SNSRXCFG_330.exe] and run.
# Select your GPS (in most cases GPS 18x PC/LVC). Press F10 to switch to NMEA mode (Config > Switch to NMEA Mode)
# Select Config > Setup and choose the COM port your GPS is connected too. Leave baud rate as auto for now, OK.
# Select Comm > Connect to connect to the GPS.
# Go to Config > Get Configuration from GPS to download it's current configuration
# Click File > Save to save the current configuration
# In Config > Sensor Configuration change the Baud Rate to 9600. You can also check to make sure 1PPS is enabled here too. Click OK.
# Hitting F7 when in the main window of the software also brings up the GPS sentences to output if that is of interest.
# File > Save to a different file than step 5.
# Press F9 or Config > Send Configuration to GPS. This will then send all the changes you made to the GPS unit (including baud rate so a reconnect may be needed)
===uBlox GPS===
You can use uBlox GPS modules with the VOTER/RTCM. The ones readily available usually have a 5 pin header on them (5V, GND, TXD, RXD, PPS), as well as an integrated patch antenna, and a SMA connector for an external antenna.
Data is TTL, so make sure to set the jumpers inside the RTCM for TTL data. Baud rate is 9600 by default, and uses NMEA. Set those accordingly in the configuration menu.
The RTCM and VOTER require different settings for data and PPS polarity. The VOTER wants '''inverted''' for both, and the RTCM wants '''non-inverted''' for both.
Make sure to save (99) and reboot (r) your VOTER/RTCM after making changes for them to be effective.
===PPS Issues===
If your VOTER/RTCM connects to your server, but it won't receive anything, check/toggle the PPS polarity, it may be incorrect.
===NMEA <--> TSIP Mode Change===
If you change from NMEA to TSIP (or vice versa), the VOTER/RTCM tries to be smart and change the baud rate for you. For TSIP, it sets it to 9600, and for NMEA it sets it to 4800. However, '''it also resets GPS and PPS polarity to 0'''! This WILL cause you confusion, if you are trying to find the right set of settings for your GPS. This will probably be removed in a future firmware version.
If you want to use a mix client (non-voted), make sure that receiver's configuration line in voter.conf '''does not''' have the '''master''' option set.
If you want to use a mix client (non-voted), make sure that receiver's configuration line in voter.conf '''does not''' have the '''master''' option set.
==Mix Clients with Voted Client Issues==
Situation...
"I have a private node with 6 voted receivers using RTCMs. I'd like to add a 7th RTCM to this node that is always mixed in rather than voted. I'm able to make this RTCM work as a 7th voted receiver with no problem. Everything I've read seems to indicate that if I change GPS PPS polarity to "none" this will achieve my desired results, however I am unable to get audio out of my transmit RTCM from this 7th site. It does change color to cyan in Allmon indicating it is non voted input but I do not get any indication or audio when that units COR goes active."
"Setting voter debug level 3 in Asterisk and I'm seeing the following message repeatedly scrolling by in a blur when the mix client detects COR (COR is active). Sequence numbers are continually incrementing by 1. I'm running software version 1.47 on all my clients:"
<pre>
mix client (Mulaw) my_client index:0 their seq:629 our seq:629
mix client my_client outa bounds, resetting!!
</pre>
If you have a similar situation to the above... check your buflen in voter.conf. Make sure it is at >=160 and see if that fixes it.
So, the 1 after ok is the "happy gps" flag. The other 5 bytes are supposed to be bytes 9-14 from the packet... sort of. They are bytes 9-14 of the buffer, but they are actually bytes 8-13 of the binary message.
So, the 1 after ok is the "happy gps" flag. The other 5 bytes are supposed to be bytes 9-14 from the packet... sort of. They are bytes 9-14 of the buffer, but they are actually bytes 8-13 of the binary message. '''Note that array byte 12 is Minor Alarm bits 0-7, and byte 11 is Minor Alarm bits 8-12.'''
GPS-DEBUG: TSIP: ok 1, 9 - 14: 00 00 00 00 00 00 - everything is good in the 'hood, Doing Fixes, Phase Locking
GPS-DEBUG: TSIP: ok 1, 9 - 14: 00 00 00 00 00 00 - everything is good in the 'hood, Doing Fixes, Phase Locking
GPS-DEBUG: TSIP: ok 0, 9 - 14: 00 00 00 18 08 06 - not happy, Not Tracking Satellites, Not Disciplining Oscillator (0x18 --> 0b000000011000), No Usable Sats, Inactive
GPS-DEBUG: TSIP: ok 0, 9 - 14: 00 00 00 18 08 06 - not happy, Not Tracking Satellites, Not Disciplining Oscillator (0x18 --> 0b00011000, Bits 7-->0 of Minor Alarms), No Usable Sats, Inactive
GPS-DEBUG: TSIP: ok 0, 9 - 14: 00 00 00 08 08 05 - not happy, Not Tracking Satellites, No Useable Sats, Compensating OXCO (holdover)
GPS-DEBUG: TSIP: ok 0, 9 - 14: 00 00 00 08 08 05 - not happy, Not Tracking Satellites, No Useable Sats, Compensating OXCO (holdover)
GPS-DEBUG: TSIP: ok 0, 9 - 14: 00 00 00 00 00 04 - not happy, Initializing Loop Filter
GPS-DEBUG: TSIP: ok 0, 9 - 14: 00 00 00 00 00 04 - not happy, Initializing Loop Filter
GPS-DEBUG: TSIP: ok 0, 9 - 14: 00 00 08 08 08 00 - not happy, Almanac Not Complete, Not Tracking Satellites, No Useable Sats
GPS-DEBUG: TSIP: ok 0, 9 - 14: 00 00 08 00 00 00 - not happy, Almanac Not Complete
GPS-DEBUG: TSIP: ok 0, 9 - 14: 00 00 08 08 01 00 - not happy, Almanac Not Complete, Not Tracking Satellites, Don't Have GPS Time
GPS-DEBUG: TSIP: ok 0, 9 - 14: 00 00 00 0A 08 00 - not happy, Antenna Open, Not Tracking Satellites, No Useable Sats
</pre>
</pre>
*Any Critical Alarms.
*Any Critical Alarms.
*Any Minor Alarms.
*Any Minor Alarms.
=Ubiquity ToS=
=Ubiquity ToS=
==Radio Hardware==
==Radio Hardware==
For best results, you should use all identical RF equipment between your voting RX sites and simulcast TX sites. If you don't, you can end up with strange audio artifacts when different receivers are used, and other strange audio issues when different transmitters are used.
For best results, you should use all identical RF equipment between your voting RX sites and simulcast TX sites. If you don't, you can end up with strange audio artifacts when different receivers are used, and other strange audio issues when different transmitters are used. The most important thing when setting your levels is that ALL the RX and TX levels match from radio to radio. The best way this is achieved is using a "master" radio and reference from that - all radios might be identical models, but may not have identical audio characteristics so check those levels! Also check CTCSS and audio levels separately to make sure they all match.
Of course Duplex Mode 3 support can't be used with voting or simulcast. You also loose Touch Tone muting, Time Out Timer and Repeater Disable functions because the repeat path is not through app_rpt.
Of course Duplex Mode 3 support can't be used with voting or simulcast. You also loose Touch Tone muting, Time Out Timer and Repeater Disable functions because the repeat path is not through app_rpt.
= Setting Voter Buffers =
Voter ping is useful for end-to-end network evaluation when ICMP ping is turned off and/or the RTCM is behind a firewall and is not ICMP reachable. It can also help with finding the correct RTCM and voter.conf buffer settings.
=== Voter Ping Usage ===
The voter ping asterisk CLI syntax is:
*CLI>voter ping nameOfClient [packetCount]
If packetCount is not specified 8 pings will be sent. Use packetCount of 0 to stop an in progress voter ping. Set packetCount to at least 100 when evaluating link quality.
The result will be similar to:
...
PING (nameOfClient): Packets tx: 100, rx: 100, oos: 0, Avg.: 26.710 ms
PING (nameOfClient): Worst: 38 ms, Best: 22 ms, 100.0% Packets successfully received (0.0% loss)
The output above is self evident except for oos which is a count of out of sequence packets. Voter ping requires RTCM firmware 1.23 or newer and chan_voter 2013-08-04 or newer.
=== RX Buffer Size ===
Ping all the receiver sites and look for the worst response of the worst client. As a rough rule of thumb the buflen setting in voter.conf should be set to the worst response + 40ms or 120 whichever is greater. Using the above case the buflen should be set to 120 (38+40
=== TX Buffer Size ===
Ping all the transmitter sites and look for the worst response of the worst client. The RTCM TX Buffer Length should be set to (worst response + 40ms) * 8 or 480 whichever is greater. Using the above case the RTCM TX Buffer Length should be set to 624 ((38+40)*8).
=== Assumptions ===
* The minimum TX buffer size is 480 (60ms) and the minimum RX buffer is 120ms. These were derived by testing on a LAN segment with chan_voter 2013-08-04 and RTCM 1.26.
* The ping times are not round trip times but they are in fact round trip times. Therefore the worst response could (should?) be divided by 2. Ie RX buffer = 38/2+40=59 and TX buffer = (38/2 + 40) * 8 = 472. Minimums still apply.
* The internet path to and from the RTCM under test is symmetrical.
* The added 40ms pad is an estimate of buffer ingress and egress.
As always your milage may vary. Some trial and error may be required to find the optimum settings.
=== Setup ===
The RX buffer is set with buflen=120 in /etc/asterisk/voter.conf. The value is in milliseconds. The TX buffer is set in the RTCM with menu item 7. The value is in 125 microsecond increments. To match the size of the TX to the RX buffer, use the RX buffer * 8 to get the TX buffer size.
[[Category:How to]]
[[Category:Node Configuration]]