Соединение с провайдером в лучшем случае на 31200 б/с. С другим модемом было 44000. Как можно исправить эту проблему?

Нет статистики для анализа, см. например здесь
http://www.dlink.ru/phorum/viewtopic.php?t=7582

_________________
Added and original personal edition for RV aka rvn 2006

Драйвера поставил свежие с http://tsd.dlink.com.tw
Вот такая статистика у модема:

at&v1
TERMINATION REASON.......... LOCAL REQUEST
LAST TX rate................ 28800 BPS
HIGHEST TX rate............. 28800 BPS
LAST RX rate................ 31200 BPS
HIGHEST RX rate............. 31200 BPS
PROTOCOL.................... LAPM
COMPRESSION................. V44
Line QUALITY................ 043
Rx LEVEL.................... 026
Highest Rx State............ 67
Highest TX State............ 67
EQM Sum..................... 0019
RBS Pattern................. FF
Rate Drop................... FF
Digital Loss................ None
Local Rtrn Count............ 00
Remote Rtrn Count........... 00
Flex fail 9481834246E0

OK


at&v2
Connection time : 02:11:55
Handshake Time/Retries : 21 sec/0
TX Rate (Last/Init/Min/Max) : 28800/28800/28800/28800
RX Rate (Last/Init/Min/Max) : 31200/31200/31200/31200
Modulation/Protocol/Compression : V.34/LAPM/V.44
TX Symbol rate : 3200
TX/RX carrier frequency, Hz : 1829/1829
Signal Level (TX/Power Drop), -dB : 5/1
RX Signal Level (Last/Min/Max), -dB : 24/24/24
Band Edge Lower/Upper, Hz : 150/3825
Round trip delay, ms : 2.563
EQM Value (Last/Min/Max/Negative) : 43/28/55/0
EQM Samples Running Sum : 0019
EQM Last 10 Readings : 42 49 46 42 45 45 43 45 42 41
SNR Ratio (Last/Min/Max), dB : 46/46/46
TX/RX Non-linear Encoding : OFF/ON
TX/RX Precoding : OFF/ON
TX/RX Constellation Shaping : OFF/ON
TX Trellis Encoding : 16 state
TX Pre-emphasis : 0
TX/RX state (Max TX/RX, Last TX/RX) : 67H/67H, 67H/67H
Error Correction Status : ODP:T ADP:R SABME:T UA:R XID:T,R SYNC
Dual PCM/120 Hz detection : Yes/No
Energy at 3750Hz/Average Energy : 882/945
Retrains (Issued/Granted/Fast) : 0/0/0
Renegs (Issued/Granted) : 0/0
Retrans per frame/Frames rejected : 1/33
Total number of REJ sent/received : 33/255 or more
Last Retrain/Reneg reason : None
Last Retrain/Reneg requested : None
Minutes Since Last Retrain/Reneg : 131
Fallback to V34 reason : Data Pump early decision to FB to V34
Disconnect reason : LOCAL REQUEST
Remote Manufacturer/Licensee Code : Conexant/Conexant
Remote Manufacturer's Product Caps : K56Flex, V.90
Remote V.8bis caps (type) : Digital (Server)
Remote V.8bis caps (K56Flex mode) : K56Flex prototype mode not supported
Remote V.8bis caps (K56Flex version): 1.1
Remote K56Flex RAM version supported: 70
Remote Coding used/forced by server : A-law/Yes
Remote controller version number : 0
Remote supports symbol rate (1,2,5) : 2743:ON 2800:ON 3429:ON 3429-TX:ON
Remote supports symbol rate (3,4) : 3000-L:ON 3000-H:ON 3200-L:ON 3200-H:ON
Remote power drop support : ON
Remote max symbol rate difference : 0 steps
Remote is a CME modem : No
Remote supports V.34bis : Yes
Remote frequency source : External
CRe/CRd/CL/MS/ACK/NAK received : Yes/No/Yes/No/Yes/No
V.8bis success/V.8bis neg started : Yes/Yes
Quick Connect Info0 : Both modems indicate V.92 in INFO0
Call waiting count during connetion : 0
Last MOH Condition State : Idle wait for MOH action
Last MOH Datapump State TX : Sending A/B "Retrain State"
Last MOH Datapump State RX : Unknown


at#ud
Diag Command Specification rev.: 1.0
Call Setup Result code : Data Answering signal detected
Multi-media mode : Data Only
DTE-DCE interface mode : Async data
TX/RX signal power level, -dBm : 5/26
Estimated noise level, -dBm : 27
TX/RX Negotiation : V.34/V.34
TX/RX Symbol Rate : 3200/3200
TX/RX Carrier frequency, Hz : 1829/1829
TX data rate (Last/Init) : 28800/28800
RX data rate (Last/Init) : 31200/31200
Temporary carrier loss count : 0
Carrier Rate Re-neg count : 0
Retrains Requested/Granted : 0/0
Protocol/Compression : V.42 LAPM/V.42bis
Error control frame size, bytes: 128
Error control timeouts in TX : 8
Error control NAKs received : 111
TX/RX flow control : V.24 ckt 106/133 / V.24 ckt 106/133
TX/RX chars sent : 3194048/29975814
TX/RX chars lost (data overrun): 0/0
TX/RX I-Frame count : 87824/222096
TX/RX I-Frame error count : 367/33
Termination Cause : cct108 turned Off

Для начала отключи детектор двойного аналого-цифрового преобразования.

как управлять параметром Dual PCM?
скачал с сайта acorp мануал по AT командам к модему Acorp EMSF2 - там не нашел описания этого параметра...

Читай внимательнее
S202
Bit 3 – Отладочный режим
Bit 4 - Автоматический вывод AT&V2 в начале и в конце передачи данных.
Bit 5 – Запретить работу детектора двойного аналогово-цифрового преобразования. Иногда помогает восстановить работу на протоколе V.90\V.92, если модем ошибочно выбирает протокол V.34.

Тебя интересует пятый бит. Сам пересчитаешь что нужно записать в S202?

Вот такая инит строка: ATS202=32+PIG=0

ati1
255

OK
ati2
OK
ati3
ACF3_V1.900P-V90_P21_FSH

(При перепрошивке на эту версию проблема с busy исчезает)

OK
ati4
a007040284C6002F

bC60000000

r1005111151012000

r3000111170000000

OK
ati5
B5

OK
ati6
RCV56DPF-PLL L8773A Rev 62.01/62.01
OK
ati7
OK


at&v
ACTIVE PROFILE:
B0 E1 L1 M1 N0 P Q0 V1 W2 X4 Y0 &C1 &D2 &G0 &J0 &K3 &Q5 &R1 &S0 &T5 &X0 &Y0
S00:000 S01:000 S02:043 S03:013 S04:010 S05:008 S06:002 S07:060 S08:002 S09:006
S10:014 S11:085 S12:050 S18:000 S25:005 S26:001 S36:007 S38:020 S46:138 S48:007
S95:044

STORED PROFILE 0:
B1 E1 L1 M1 N0 Q0 T V1 W0 X4 Y0 &C1 &D2 &G0 &J0 &K3 &Q5 &R1 &S0 &T5 &X0
S00:000 S02:043 S06:002 S07:050 S08:002 S09:006 S10:014 S11:085 S12:050 S18:000
S36:007 S40:104 S41:195 S46:138 S95:000

STORED PROFILE 1:
B1 E1 L1 M1 N0 Q0 T V1 W0 X4 Y0 &C1 &D2 &G0 &J0 &K3 &Q5 &R1 &S0 &T5 &X0
S00:000 S02:043 S06:002 S07:050 S08:002 S09:006 S10:014 S11:085 S12:050 S18:000
S36:007 S40:104 S41:195 S46:138 S95:000

TELEPHONE NUMBERS:
0= 1=
2= 3=

OK
at&v1
TERMINATION REASON.......... LOCAL REQUEST
LAST TX rate................ 26400 BPS
HIGHEST TX rate............. 26400 BPS
LAST RX rate................ 33333 BPS
HIGHEST RX rate............. 33333 BPS
PROTOCOL.................... LAPM
COMPRESSION................. V44
Line QUALITY................ 024
Rx LEVEL.................... 013
Highest Rx State............ 67
Highest TX State............ 67
EQM Sum..................... 0103
RBS Pattern................. 00
Rate Drop................... FF
Digital Loss................ 2000
Local Rtrn Count............ 00
Remote Rtrn Count........... 00
V90 9481834246E0

OK


at&v2

Connection time : 00:01:37
Handshake Time/Retries : 23 sec/0
TX Rate (Last/Init/Min/Max) : 26400/26400/26400/26400
RX Rate (Last/Init/Min/Max) : 33333/33333/33333/33333
Modulation/Protocol/Compression : V.90/LAPM/V.44
TX Symbol rate : 3200
Signal Level (TX/Power Drop), -dB : 10/1
RX Signal Level (Last/Min/Max), -dB : 13/13/13
Band Edge Lower/Upper, Hz : 150/3825
Round trip delay, ms : 3.188
EQM Value (Last/Min/Max/Negative) : 24/20/27/0
EQM Samples Running Sum : 0103
EQM Last 10 Readings : 22 24 23 21 24 22 24 23 24 21
SNR Ratio (Last/Min/Max), dB : 46/46/46
TX Non-linear Encoding : OFF
TX Precoding : OFF
TX/RX Constellation Shaping : OFF/OFF
TX Trellis Encoding : 16 state
TX Pre-emphasis : 0
TX/RX state (Max TX/RX, Last TX/RX) : 67H/67H, 67H/67H
Error Correction Status : SABME:T UA:R XID:T,R SYNC
Dual PCM/120 Hz detection : No/No
Energy at 3750Hz/Average Energy : 906/0
RBS Pattern/Alternating RBS Pattern : 00/NA
V.90 Digital Pad/A-law/HighPowerSrv : 0dB/No/No
Retrains (Issued/Granted/Fast) : 0/0/0
Renegs (Issued/Granted) : 0/0
Retrans per frame/Frames rejected : 1/0
Total number of REJ sent/received : 0/0
Last Retrain/Reneg reason : None
Last Retrain/Reneg requested : None
Minutes Since Last Retrain/Reneg : 1
Disconnect reason : LOCAL REQUEST
Remote Manufacturer/Licensee Code : Conexant/Conexant
Remote Manufacturer's Product Caps : K56Flex, V.90
Remote V.8bis caps (type) : Digital (Server)
Remote V.8bis caps (K56Flex mode) : K56Flex prototype mode not supported
Remote V.8bis caps (K56Flex version): 1.1
Remote K56Flex RAM version supported: 70
Remote Coding used/forced by server : A-law/Yes
Remote controller version number : 0
Remote supports symbol rate (1,2,5) : 2743:ON 2800:ON 3429:ON 3429-TX:ON
Remote supports symbol rate (3,4) : 3000-L:ON 3000-H:ON 3200-L:ON 3200-H:ON
Remote power drop support : ON
Remote max symbol rate difference : 0 steps
Remote is a CME modem : No
Remote supports V.34bis : Yes
Remote frequency source : External
Remote is ITU/K56Flex neg/High IMD : Yes/No/No
V.8 bis CRe detected/early : Yes/No
CRe/CRd/CL/MS/ACK/NAK received : Yes/No/Yes/No/Yes/No
V.8bis success/V.8bis neg started : Yes/Yes
Quick Connect Info0 : New QC Profile saved
Quick Connect Info0 : Both modems indicate V.92 in INFO0
Call waiting count during connetion : 0
Last MOH Condition State : Idle wait for MOH action
Last MOH Datapump State TX : Sending A/B "Retrain State"
Last MOH Datapump State RX : Unknown
PCM Upstream RBS2 Detection : Unknown
PCM Phase4 Upstream Const./RR : 4-point/4-point
PCM Upstream Pad Detection : 0dB




at#ud

Diag Command Specification rev.: 1.8
Call Setup Result code : Data Answering signal detected
Multi-media mode : DSVD, 1.2
DTE-DCE interface mode : Async data
TX/RX signal power level, -dBm : 10/13
Estimated noise level, -dBm : 27
TX/RX Negotiation : V.34/V.90 Issue 1 (asymmetric)
TX/RX Symbol Rate : 3200/8000
TX/RX Carrier frequency, Hz : 1829/0
TX data rate (Last/Init) : 26400/26400
RX data rate (Last/Init) : 33333/33333
Temporary carrier loss count : 0
Carrier Rate Re-neg count : 0
Retrains Requested/Granted : 0/0
Protocol/Compression : V.42 LAPM/V.42bis
Error control frame size, bytes: 128
Error control timeouts in TX : 0
Error control NAKs received : 0
TX/RX flow control : V.24 ckt 106/133 / V.24 ckt 106/133
TX/RX chars sent : 8729088/36252416
TX/RX chars lost (data overrun): 0/0
TX/RX I-Frame count : 139776/246784
TX/RX I-Frame error count : 0/0
Termination Cause : Dte Hangup Command

На V90 уже заработал, далее у тебя очень высокий уровень как входного так и выходного сигналов. Увы в прошивке с отсутствием регулировок это не лечится