The following is from a ZyXEL VMG1312-B10A, used on a VDSL2 service which, in turn, is provisioned on the Openreach 40/10 Mbps product.
The "help" output is (obviously) xDSL service type agnostic --
> xdslctl --help
Usage: xdslctl start [--up] <configure command options>
xdslctl stop
xdslctl connection [--up] [--down] [--loopback] [--reverb]
[--medley] [--noretrain] [--L3] [--diagmode] [--L0]
[--tones <r1-r2,r3-r4,...>] [--normal] [--freezeReverb] [--freezeMedley]
xdslctl configure/configure1 [--mod <a|d|l|t|2|p|e|m|M3|M5|v>] [--lpair <(i)nner|(o)uter>]
[--trellis <on|off>] [--snr <snrQ4>] [--bitswap <on|off>] [--sesdrop <on|off>]
[--sra <on|off>] [--CoMinMgn <on|off>] [--i24k <on|off>] [--phyReXmt <0xBitMap-UsDs>]
[--Ginp <0xBitMap-UsDs>] [--TpsTc <0xBitMap-AvPvAaPa>] [--monitorTone <on|off>]
[--profile <0x00 - 0xFF>|<"8a |8b |8c |8d |12a |12b |17a |30a">] [--us0 <on|off>]
[--dynamicD <on|off>] [--dynamicF <on|off>] [--SOS <on|off>] [--maxDataRate <maxDsDataRateKbps maxUsDataRateKbps maxAggrDataRateKbps>]
[--forceJ43 <on|off>] [--toggleJ43B43 <on|off>]
xdslctl bert [--start <#seconds>] [--stop] [--show]
xdslctl afelb [--time <sec>] [--tones] [--signal <1/2/8>]
xdslctl qlnmntr [--time <sec>] [--freq <msec>]
xdslctl inm [--start <INMIATO> <INMIATS><INMCC><INM_INPEQ_MODE><INM_INPEQ_FORMAT>] [--show]
xdslctl snrclamp [--shape <shapeId>] [--bpshape [bpIndex-bpLevel,]]
xdslctl nlnm [--show ] [--setThld <Thld_Num_Tones>]
xdslctl diag [--logstart <nBytes>] [--logpause] [--logstop] [--loguntilbufferfull <nBytes>] [--loguntilretrain <nBytes>] [--dumpBuf <sizeKb>]
xdslctl ntr [--start [output freq(default is 8000)]] [--stop]
xdslctl info [--state] [--show] [--stats] [--SNR] [--QLN] [--Hlog] [--Hlin] [--HlinS] [--Bits]
[--pbParams] [--linediag] [--linediag1] [--reset] [--vendor] [--cfg] [--webstats]
xdslctl profile [--show] [--save] [--restore]
xdslctl --version
xdslctl --help
>
This output is for a VDSL2 service --
> xdslctl info --cfg
xdslctl: ADSL driver and PHY status
Status: Showtime
Last Retrain Reason: 0
Last initialization procedure status: 0
Max: Upstream rate = 18534 Kbps, Downstream rate = 44755 Kbps
Bearer: 0, Upstream rate = 10000 Kbps, Downstream rate = 40000 Kbps
Bearer: 1, Upstream rate = 0 Kbps, Downstream rate = 0 Kbps
adslAnnexAParam: 01d04980
adslTrainingMarginQ4: -1
adslShowtimeMarginQ4: -1
adslLOMTimeThldSec: -1
adslDemodCapMask: 0090447a
adslDemodCapValue: 0090447a
adsl2Param: 00000000
adslPwmSyncClockFreq: 0
adslHsModeSwitchTime: 0
adslDemodCap2Mask: 00d00000
adslDemodCap2Value: 00d00000
vdslParam: 007f0040
vdslParam1: 00000000
xdslAuxFeaturesMask: 00000003
xdslAuxFeaturesValue: 00000003
vdslCfgFlagsMask: 00000000
vdslCfgFlagsValue: 00000000
xdslCfg1Mask: 00000000
xdslCfg1Value: 00000000
xdslCfg2Mask: 00000000
xdslCfg2Value: 00000000
xdslCfg3Mask: 00000000
xdslCfg3Value: 00000000
xdslCfg4Mask: 00000000
xdslCfg4Value: 00000000
maxDsDataRateKbps: 0
maxUsDataRateKbps: 0
maxAggrDataRateKbps: 0
xdslMiscCfgParam: 00000000
AFE_ID: 10608700 00000000
>