Attached are two text (capture) files of tests i have done; i purposely used lower case so my commands via modem would stand out from modem responses. I have the USR CD and it gives the AT command set for their modem(s). Other than the possibility of the Xn command, i see no way to set data rate. Please review those files and advise what i should try next.
** Called "wonderful" "helpful" Qwest about connection problem. The extensive phone line testing was done in Apr 2009 with complete bill of health including almost no noise; that is when the tech said that a stinger had (note tense) been installed. The idiot at Qwest maintains there is no record of that, there is no way to determine that, and that nobody there knows what i am talking about (!!). The very same idiot maintains that i can communicate at _any_ data rate even above 1M (!!) and to call my ISP about the problem.
Telco's, USWEST/QWEST included, running out of inter-office copper, had to "grandfather" the metallic 0-15 DC signal channel and discontinued the offering. It was replaced by voice-grade signal channel, and the customer had to provide their own tone hardware. Later, customers were advised of a date on which even the grandfathered channels would be discontinued.
You're overly critical. The DC signal channel was an offered service throughout the Bell System. I probably even have a copy of the Technical Publication somewhere.
You're right, the person appears to be oblivious. There is a very simple way for that phone answerer to obtain all the details of the facility assigned to your phone line. It's called, appropriate enough, the Line Assignment record.
I can't call them about this for you, because I am not your designated representative. If you have a way to conference me onto a call with them, however, I can talk with them. But it might cost you a beer at the nearest McMenamins.
You're overly critical. The DC signal channel was an offered service throughout the Bell System. I probably even have a copy of the Technical Publication somewhere.
Telco's, USWEST/QWEST included, running out of inter-office copper, had to "grandfather" the metallic 0-15 DC signal channel and discontinued the offering. It was replaced by voice-grade signal channel, and the customer had to provide their own tone hardware. Later, customers were advised of a date on which even the grandfathered channels would be discontinued.
I presume you reviewed the two ascii files attached elsewhere; i made a third try with a differrnt setting S0=1, S32=2 and the modem indicated speed 45333/26400 with protocol LAPM/SREJ (whatever that means). So i went into dial-up networking and changed the initialization string for that. The little double-monitor icon now indicates 48K which is a decided improvement. Any way i can goose it more?
OK; that is a bit different than S32=98 where i have been having trouble since the "stinger" and also different than S32=2 which seems to give me 48K, a decided improvement. Will let you know what that change does.
To see if i could control the data rate, i tried "z s0=1 s32=2 &n38" for initialization string (force 56K) and nogo; then "z s0=1 s32=2 &n36" and got 48K (supposed to force 53.3K), then "z s0=1 s32=2 &n17" and still got 48K (supposed to force 28K). So i dropped the &n and am using "z s0=1 s32=2" for now.
Do not understand the modem response speed 45333/26400 but discovered that download rate can be extremely slow IF IT EXISTS AT ALL, so i reverted to the standby "S0=0 S23=98" even tho that gives me 28.8K at best; it works in both directions. Suggestions for consistent 48K both directions?
Changing the xon character to 96 = 0x60 = ' is unlikely to be helpful. Where did you get the idea that this would be sensible?
Default is S32=17 and it would only be relevant if you were on a poxy three wire serial link without hardware handshaking. This is extremely unlikely for an internal modem. Typically they have a much larger FIFO than standard serial port chipsets and fullspeed hardware handshaking.
I strongly suggest that your problems here are largely self inflicted.
Do AT&V0 and capture the result it displays. Posting that here will give us a sporting chance of undoing the mess you have got yourself into.
Your best bet now is to reset the modem to its factory defaults (usually two variants one is robust and the other tries to be go-faster). Try each one of these in turn and you might actually get somewhere useful.
AT&F AT&F0 AT&F1
Several of the other S registers you have meddled with are either reserved or undocumented or typos in your report of what you did.
When you get it right store the best profile with AT&W0 Then initialise your modem with ATZ0
All of the following commands result in ERROR : AT&V0 , AT&F , AT&F0 and AT&F1. I did not change any character, XON or otherwise. S32=17 would disable V.34+ (value 16) and enable v.8 indicate (value
1) and certainly would not enable v.8 mode (value 2). I have an external modem; refuse to use an internal of any type as i can SEE the lights on an external modem and have a fair idea as to which way data is traveling (and how much).
S33 V.34 & V.34+ Connection setup bit mapped control flags. 1 = Disable 2400 Symbol rate 2 = Disable 2743 Symbol 4 = Disable 2800 Symbol rate 8 = Disable 3000 Symbol rate A setting of 15 would disable all of these. S34 V.34 & V.34+ Connection setup bit mapped control flags. 1 = Disable 8S-2D trellis encoding 2 = Disable 16S-4D trellis encoding 4 = Disable 32S-2D trellis encoding A setting of 7 would disable all of these. Will try.
Try AT&V or ATI4 then. Something is very fishy here...
You should be able to make the modem tell you what its settings are.
Where did you get this information? Most of the rest of the world uses different numbered S registers eg.
formatting link
S32 is the Xon character (changing it not implemented in some modems). I was also suspicious of your &N17 but put it down to careless typos. Something which incidentally does not bode well for setting S registers.
You are completely barking. Have you even got a decent FIFO buffered
16550 type serial card in this derelict PC ?
A PC of the implied vintage to be running Win98 basic serial ports cannot keep up with the modem adequately at 56k speeds without having a FIFO to absorb the slack. Dropped characters force retransmits and slows things down. If you use an internal modem the FIFO is much bigger.
The FIFO *is* a decent FIFO buffered 16550 type "serial card" emulated in the PCs ASIC; ASUS M2N-MX SE Plus clock 2700Mhz. Your "S" register descriptions are cattywhumpus with regard to Rockwell which is one of the standards - that BTW follows Hayes, another standard. AFAIK US Robotics used a Rockwell chip; cannot tear into it right now(!!).
Copy and paste of manual session; note S register info *directly* from modem: ATE1 OK ATI4 U.S. Robotics 56K FAX EXT Settings...
B0 E1 F1 M1 Q0 V1 X4 Y0 BAUD=115200 PARITY=N WORDLEN=8 DIAL=TONE ON HOOK CID=0
OK ATI11 U.S. Robotics 56K FAX EXT Link Diagnostics...
Modulation V.90 Carrier Freq (Hz) None/1920 Symbol Rate 8000/3200 Trellis Code None/64S-4D Nonlinear Encoding None/ON Precoding None/ON Shaping ON/ON Preemphasis (-dB) 5/10 Recv/Xmit Level (-dBm) 26/16 Near Echo Loss (dB) 5 Far Echo Loss (dB) 0 Carrier Offset (Hz) NONE Round Trip Delay (msec) 42 Timing Offset (ppm) 2417 SNR (dB) 46.0 Speed Shifts Up/Down 4/5 Status : uu,5,12N,12.2,-7,0N,0,49.7,15.9 OK ATI6 U.S. Robotics 56K FAX EXT Link Diagnostics...
Chars sent 2397433 Chars Received 52846317 Chars lost 0 Octets sent 1408747 Octets Received 51902644 Blocks sent 79234 Blocks Received 408326 Blocks resent 31
Retrains Requested 0 Retrains Granted 0 Line Reversals 0 Blers 2894 Link Timeouts 0 Link Naks 11
Data Compression V42BIS 2048/32 Equalization Long Fallback Enabled Protocol LAPM/SREJ Speed 45333/24000 V.90 Peak Speed 48000 Last Call 03:29:22
Disconnect Reason is DTR dropped
OK ATS$ HELP, S Register Functions (CTRL-S to Stop, CTRL-C to Cancel)
S0 Ring to Answer ON S28 V32 Handshake Time (1/10sec) S1 Counts # of Rings S29 V.21 answer mode fallback timer S2 Escape Code Char S30 Reserved S3 Carriage Return Char S31 Reserved S4 Line Feed Char S32 Connection bit mapped operations. S5 Backspace Char 1 = V.8 Call Indicate enable S6 Wait Time/Dial Tone (sec) 2 = Enable V.8 mode S7 Wait Time/Carrier (sec) 4 = Reserved S8 Comma Time (sec) 8 = Disable V.34 modulation S9 Carrier Detect Time (1/10sec) 16 = Disable V.34+ modulation S10 Carrier Loss Time (1/10sec) 32 = Disable x2 modulation S11 Dial Tone Spacing (msec) 64 = Disable V.90 modulation S12 Escape Code Time (1/50sec) 128 = Reserved S13 Bit Mapped S33 V.34 & V.34+ Connection setup 1 = Reset ON DTR Loss bit mapped control flags. 2 = Reduced Non-ARQ TX Buffer 1 = Disable 2400 Symbol rate 4 = Set DEL=Backspace 2 = Disable 2743 Symbol rate 8 = Do DS0 ON DTR 4 = Disable 2800 Symbol rate 16 = Do DS0 ON Reset 8 = Disable 3000 Symbol rate Strike a key when ready . . . 32 = Reserved 16 = Disable 3200 Symbol rate 64 = Disable Quick Retrains 32 = Disable 3429 Symbol rate 128 = Escape Code Hang Up 64 = Reserved S14 Reserved 128 = Disable Shaping S15 Bit Mapped S34 V.34 & V.34+ Connection setup 1 = MNP/V.42 Disabled in V.22 bit mapped control flags. 2 = MNP/V.42 Disabled in V.22bis 1 = Disable 8S-2D trellis encoding 4 = MNP/V.42 Disabled in V.32 2 = Disable 16S-4D trellis encoding
OK, i tore apart another, newer US Robotics FaxModem, same model 5686 and ther are a number of custom chips none of them hint at Hayes or Rockwell - so the S registers could be cattywhumpus WRT to Hayes/Rockwell.
AND..command codes, S-register info, etc are all on the CD that came with the modem; date code seems to be 08/06/2004. I will stick with the codes as shown via the CD and via the modem for sanity.
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