.TH backoff 1 "October 2018" "plc-utils-2.1.12" "Qualcomm Atheros Powerline Toolkit" .SH NAME backoff - Transmit power backoff utility for 75xx devices .SH SYNOPSIS .BR backoff .RI [ options ] .SH DESCRIPTION The Transmit power backoff utility reduces the transmit power of the device using VS_SET_PRESCALER_BACKOFF messages and prints the power backoff applied to the frequency bands. This utility can also be used to retrieve the power backoff applied to the frequency bands using VS_GET_PRESCALER_BACKOFF messages and prints it in the console. Output is column-oriented and suitable for loading into a spreadsheet or being read by a simple program. .PP This program is part of the Qualcomm Atheros Powerline Toolkit. See the \fBplc\fR man page for an overview and installation instructions. .SH CHIPSETS QCA75xx .SH OPTIONS .TP -\fBc\fI coupling\fR Tonemap coupling. Use the number \fB0\fR or the string "\fBpri\fR" for SISO primary coupling. Use the number \fB1\fR or the string "\fBalt\fR" for SISO alternate coupling. Use the number \fB2\fR or the string "\fBmimo\fR" for MIMO coupling. This program will accept any numeric value from \fB0\fR through \fB255\fR but runtime firmware will reject out-of-range values. .TP .RB - e Redirects stderr messages to stdout. By convention status and error messages are printed on stderr while primary program output is printed on stdout. This option prints all output on stdout in cases where this is desired. .TP .RB - g Read and display transmit power backoff values with VS_GET_PRESCALER_BACKOFF. Output is identical to set prescaler backoff values. .TP -\fBi \fIinterface\fR Select the host Ethernet interface. All requests are sent via this host interface and only reponses received via this host interface are recognized. The default interface is \fBeth1\fR because most people use \fBeth0\fR as their principle network connection; however, if environment string "PLC" is defined then it takes precedence over the default interface. This option then takes precedence over either default. .TP .RB - n Number of frequency bands in the input file .TP .RB - q Enter quiet mode. Progress messages are suppressed. .TP -\fBs\fI f\fR Set prescaler values from input file (f). Input file should contain only descriptor values. Maximum number of descriptor values in the input file should be 16 because VS_SET_PRESCALER_BACKOFF MME supports only 16 descriptors. .TP -\fBt \fImilliseconds\fR Read timeout in milliseconds. Values range from 0 through UINT_MAX. This is the maximum time allowed for a response. The default is shown in brackets on the program menu. .TP .RB -v Enter verbose mode. All Ethernet frames sent or received by the program are displayed on stdout. .TP .RB - x Exit program on first error with a non-zero exit code. This option allows shell scripts to detect failed or incomplete operations and take the appropriate action. .TP .RB - ? ,-- help Print program help summary on stdout. This option takes precedence over other options on the command line. .TP .RB - ! ,-- version Print program version information on stdout. This option takes precedence over other options on the command line. Use this option when sending screen dumps to Atheros Technical Support so that they know exactly which version of the Linux Toolkit you are using. .SH REFERENCES See the Qualcomm Atheros HomePlug AV Firmware Technical Reference Manual for more information. .SH EXAMPLES The following example displays the transmit power backoff applied to the given frequency bands. .PP # backoff -ieth1 -c2 -n1 -s input.txt Back-off Applied Successfully Frequency bands in Primary chain Band | Start index | Start back off(dB) | End index | End back off(dB) 0 0 0x5 21 0x5 Frequency bands in Alternate chain Band | Start index | Start back off(dB) | End index | End back off(dB) 0 0 0x5 21 0x5 .PP # backoff -ieth1 -c2 -n16 -s input.txt Back-off Applied Successfully Frequency bands in Primary chain Band | Start index | Start back off(dB) | End index | End back off(dB) 0 0 0x5 21 0x5 1 22 0xa 42 0xa 2 43 0xf 63 0xf 3 64 0x14 84 0x14 4 85 0x19 105 0x19 5 106 0x14 126 0x14 6 127 0xf 147 0xf 7 148 0xa 168 0xa 8 169 0x5 189 0x5 9 190 0xa 210 0xa 10 211 0xf 231 0xf 11 232 0x14 252 0x14 12 253 0x19 273 0x19 13 274 0x14 294 0x14 14 295 0xf 315 0xf 15 316 0xa 336 0xa Frequency bands in Alternate chain Band | Start index | Start back off(dB) | End index | End back off(dB) 0 0 0x5 21 0x5 1 22 0xa 42 0xa 2 43 0xf 63 0xf 3 64 0x14 84 0x14 4 85 0x19 105 0x19 5 106 0x14 126 0x14 6 127 0xf 147 0xf 7 148 0xa 168 0xa 8 169 0x5 189 0x5 9 190 0xa 210 0xa 10 211 0xf 231 0xf 11 232 0x14 252 0x14 12 253 0x19 273 0x19 13 274 0x14 294 0x14 14 295 0xf 315 0xf 15 316 0xa 336 0xa .PP # backoff -ieth1 -c0 -n1 -g Frequency bands in Primary chain Band | Start index | Start back off(dB) | End index | End back off(dB) 0 0 0x5 21 0x5 1 22 0xa 42 0xa 2 43 0xf 63 0xf 3 64 0x14 84 0x14 4 85 0x19 105 0x19 5 106 0x14 126 0x14 6 127 0xf 147 0xf 7 148 0xa 168 0xa 8 169 0x5 189 0x5 9 190 0xa 210 0xa 10 211 0xf 231 0xf 11 232 0x14 252 0x14 12 253 0x19 273 0x19 13 274 0x14 294 0x14 14 295 0xf 315 0xf 15 316 0xa 336 0xa Frequency bands in Alternate chain Band | Start index | Start back off(dB) | End index | End back off(dB) 0 0 0x5 21 0x5 1 22 0xa 42 0xa 2 43 0xf 63 0xf 3 64 0x14 84 0x14 4 85 0x19 105 0x19 5 106 0x14 126 0x14 6 127 0xf 147 0xf 7 148 0xa 168 0xa 8 169 0x5 189 0x5 9 190 0xa 210 0xa 10 211 0xf 231 0xf 11 232 0x14 252 0x14 12 253 0x19 273 0x19 13 274 0x14 294 0x14 14 295 0xf 315 0xf 15 316 0xa 336 0xa .SH DISCLAIMER Atheros HomePlug AV Vendor Specific Management Message Entry structure and content is proprietary to Qualcomm Atheros, Ocala FL USA. Consequently, public information may not be available. Qualcomm Atheros reserves the right to modify message structure and content in future firmware releases without any obligation to notify or compensate users of this program. .SH SEE ALSO .BR PLC ( 1 ), .BR backoff1 ( 1 ), .SH CREDITS Nisha K Kalaivani Somasundaram ' '