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* MTA128NT External ISDN Terminal Adapter Firmware Information *
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Contents:
1) MTA128NT Rev. E+ Firmware History
2) Support Information


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* 1 **      MTA128NT Firmware History     *
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Note: All references to 'TA' refer to the MTA128NT Rev. E+.


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MTA128NT firmware release version 8.04k
 Timestamp = 02-04-2006 14:07
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a) Features Added/Removed/Modified since 8.03:

* (02/03/2006)--Added S-register S114:
   S-Register:  S114
   Usage:       S114=n; S114?
   Function:    Minimum Baud Rate for RxRDY- to Control CTS
   Unit:        decimal ASCII code
   Range:       n=8  (57600 baud),
                n=9  (115200 baud),
                n=10 (230400 baud),
                n=11 (460800 baud),
                n=12 (disable capability)
   Default:     12 (disable capability)
   Description: The UART has the capability to co-control the CTS signal with its RxRDY- signal in order to help improve hardware flow control performance and to help avoid possible UART receiver overruns. However, it is possible that some systems will not react well to this type of control and thus this S-register can be used to enable or disable this capability depending on what works best. In general, baud rates of 230400 or higher would be the only ones that would benefit from this capability if it does not adversely affect the host system.

* (01/31/2006)--Modified S-register S37's default value:
   S-Register:  S37
   Usage:       S37=n; S37?
   Function:    SLIC Programming Options
   Unit:        decimal ASCII code
   Range:       n=0--Vring-rms=-39.00 V, Vcm=3.0 V, Vbat=-55.71 V, Fs=120 KHz,
                n=1--Vring-rms=-52.50 V, Vcm=3.0 V, Vbat=-52.50 V, Fs=120 KHz,
                n=2--Vring-rms=-40.00 V, Vcm=3.0 V, Vbat=-55.71 V, Fs=130 KHz,
                n=3--Vring-rms=-45.00 V, Vcm=3.0 V, Vbat=-62.68 V, Fs=130 KHz,
                n=4--Vring-rms=-52.50 V, Vcm=3.0 V, Vbat=-73.13 V, Fs=130 KHz,
                n=5--Vring-rms=-46.50 V, Vcm=3.0 V, Vbat=-64.77 V, Fs=150 KHz,
                n=6--Vring-rms=-45.00 V, Vcm=3.0 V, Vbat=-62.68 V, Fs=160 KHz
   Default:     5 (Vring-rms=-46.50 V, Vcm=3.0 V, Vbat=-64.77 V, Fs=150 KHz)
   Description: Various SLIC configuration options can affect the audio quality and/or ringing power. By making this S-register available, many different settings can be changed that may improve a specific characteristic of the POTS port. This S-register is stored as soon as it is accepted by the TA and so AT&W is not required. However, this S-register does NOT get restored to the default value by AT&W1Z (or AT&W1*FS1) but it will be restored to the default value by a firmware upgrade if the firmware upgrade's SAVED_PROFILE value is different from the TA's SAVED_PROFILE value at that time (SAVED_PROFILE is a value in the firmware that indicates the version of the structure of the data in the non-volatile RAM).

* (01/17/2006)--Added UART statistics to ATL8.

* (12/21/2005)--Added S-register S37:
   S-Register:  S37
   Usage:       S37=n; S37?
   Function:    SLIC Programming Options
   Unit:        decimal ASCII code
   Range:       n=0--Vring-rms=-39.00 V, Vcm=3.0 V, Vbat=-55.71 V, Fs=120 KHz,
                n=1--Vring-rms=-52.50 V, Vcm=3.0 V, Vbat=-52.50 V, Fs=120 KHz,
                n=2--Vring-rms=-40.00 V, Vcm=3.0 V, Vbat=-55.71 V, Fs=130 KHz,
                n=3--Vring-rms=-45.00 V, Vcm=3.0 V, Vbat=-62.68 V, Fs=130 KHz,
                n=4--Vring-rms=-52.50 V, Vcm=3.0 V, Vbat=-73.13 V, Fs=130 KHz,
                n=5--Vring-rms=-46.50 V, Vcm=3.0 V, Vbat=-64.77 V, Fs=150 KHz,
                n=6--Vring-rms=-45.00 V, Vcm=3.0 V, Vbat=-62.68 V, Fs=160 KHz
   Default:     3 (Vring-rms=-45.00 V, Vcm=3.0 V, Vbat=-62.68 V, Fs=130 KHz)
   Description: Various SLIC configuration options can affect the audio quality and/or ringing power. By making this S-register available, many different settings can be changed that may improve a specific characteristic of the POTS port. This S-register is stored as soon as it is accepted by the TA and so AT&W is not required. However, this S-register does NOT get restored to the default value by AT&W1Z (or AT&W1*FS1) but it will be restored to the default value by a firmware upgrade if the firmware upgrade's SAVED_PROFILE value is different from the TA's SAVED_PROFILE value at that time (SAVED_PROFILE is a value in the firmware that indicates the version of the structure of the data in the non-volatile RAM).

* (12/01/2005)--Modified S-register S39:
   S-Register:  S39
   Usage:       S39=n; S39?
   Function:    Ring-signal Peak-to-Peak Voltage (Rev. E+ only)
   Unit:        1 Volt
   Range:       n=46-59 (46-59 V)
   Default:     59 (59 V)
   Description: S39 allows the peak-to-peak voltage of the ring-signal to be chosen. This S-register is only available to the Rev. E+ hardware.

* (11/30/2005)--Modified command %Sn:
   Command:     %Sn
   Function:    Serial Port Mode
   Unit:        Decimal ASCII code
   Values:      n=0--Autobaud Mode (300-230400 baud),
                n=1--Top Speed Mode (460800 baud),
                n=2--Fixed Speed Mode (300-230400 baud)
                n=3--Fixed Speed, Parity, Data Bits, Stop Bits Mode
   Default:     %S0 (Autobaud Mode)
   Description: Typically, in command mode the TA selects a serial port speed of 300, 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200, or 230400 baud, depending on how fast the AT commands are coming from the computer or terminal. Using the %Sn command, you can disable automatic speed selection and lock the serial port speed to 460800 baud (%S1) or lock the serial port speed to the last detected speed (%S2). When the %S2 command is given, the TA locks the serial speed to the speed at which the %S2 command was given and it also changes the $SBn setting accordingly. If %S2 is stored by using &W0, then when the TA powers up it will use the speed given by $SBn and immediately enter the fixed speed mode. %S3 is similar to %S2, except that %S3 uses $SBn for the serial speed, @P3=n for the parity, @P4=n for the number of data bits, and @P6=n for the number of stop bits. The %S3 mode is useful for situations where autobauding doesn't completely detect or correctly detect all parameters of the incoming data. The serial port speed remains locked until the TA receives a %S0 command or it is shut off without storing %S1, %S2, or %S3. Another method for changing from top speed mode (%S1) or fixed speed mode (%S2 or %S3) back to autobaud mode (%S0) is to send a break or type a character ('@' works best) at a slow baud rate (such as 9600 baud) within the first 10 seconds after power-up of the TA. This fixed-speed escape method is for situations where the TA was configured for the top baud rate of the TA and stored by using &W0. If the TA is used by a computer or terminal that cannot operate at the top baud rate of the TA, then this escape method must be used to recover autobaud mode (%S0) and be sure to store %S0 using &W0 if the TA will no longer be using the top speed or fixed speed modes.

* (11/16/2005)--Modified S-register S152:
   S-Register:  S152
   Usage:       S152=n; S152?
   Function:    Maximum PPP or SoftBond Buffer Size
   Unit:        1 byte
   Range:       n=64-1500
   Default:     1500 (bytes, default PPP MRU)
   Description: S152 allows the maximum buffer size for PPP/ML-PPP (!Z=9) or SoftBonding (!Z=8) to be customized. By decreasing the frame size then response times can be increased for situations where a 1500-byte packet may cause too much delay. For SoftBonding (!Z=8) there is a 12-byte padding in each buffer so, for example, setting S152=64 would result in a data payload of 52 bytes and setting S152=1500 the data payload is 1488. This padding is not needed for PPP/ML-PPP (!Z=9), so S152=64 carries a data payload of 64 bytes.

* (08/10/2005)--Added S-register S152:
   S-Register:  S152
   Usage:       S152=n; S152?
   Function:    Maximum SoftBond Buffer Size
   Unit:        1 byte
   Range:       n=64-1500
   Default:     1500 (bytes)
   Description: S152 allows the maximum buffer size for SoftBonding (!Z=8) to be customized. By decreasing the frame size then response times can be increased for situations where a 1500-byte packet may cause too much delay. There is a 12-byte padding in each buffer so, for example, setting S152=64 would result in a data payload of 52 bytes and setting S152=1500 the data payload is 1488.


b) Test/Debug Features Added/Removed/Modified since 8.03:

* (10/06/2005)--Modified test command *RSn:
   Command:     *RSn
   Function:    Test RS-232 Handshake Signals
   Unit:        Decimal ASCII code
   Values:      n=10--Negate CTS,
                  11--Assert CTS,
                n=20--Negate DSR,
                  21--Assert DSR,
                n=30--Negate DCD,
                  31--Assert DCD,
                n=40--Negate RI,
                  41--Assert RI,
                n=50--Check RTS,
                n=60--Check DTR
   Default:     *RS0 (does nothing)
   Description: *RSn is a test command that is used to check the RS-232 hardware handshake signals. CTS, DSR, DCD, and RI can be asserted or negated and then checked by an external device for proper function. RTS and DTR can be checked with an output message of "NEGATED" indicating the signal is negated or an output message of "ASSERTED" indicating the signal is asserted.


c) Bugs fixed since 8.03:

* (02/04/2006)--Fixed a problem where getting a fatal error while servicing the UART would cause the TA to not accept AT commands after the reset.

* (02/03/2006)--To help improve throughput of bursty data at 230400 baud the TA now checks for received data at the UART every 10 ms instead of every 20 ms. Baud rates of 115200 baud and slower still check every 20 ms.

* (02/03/2006)--Fixed a long-standing potential (and possibly realized) bug related to transmitting data from the UART. It was possible for this bug to transmit data out of order and to free a buffer that was in use elsewhere. This bug relied upon a very specific and timing-critical sequence of events in order for this bug to occur.

* (02/03/2006)--Disabled the ability of the UART RxRDY- line to co-control the CTS signal due to problems some systems may have with this capability (too many changes on CTS might overwhelm some systems) S-register S114 was added to allow the user to control whether this capability is enabled or disabled. Previously this capability was enabled only for baud rates of 230400 baud and higher (S114=10). Now this capability will be disabled by default (S114=12).

* (02/02/2006)--Fixed PCM law setting when enabling PCM for SLIC. This bug was introduced when attempting to fix the possibility of the PCM law setting becoming corrupted when enabling or disabling PCM transfers.

* (02/01/2006)--Fixed an initialization bug for S-register S37 when BOOT_SWITCH is not the default value or it is not the expected SAVED_PROFILE value. This problem would have affected new production units. It also would have affected firmware upgrades if the SAVED_PROFILE value was updated to reflect changes to the stored parameters due to firmware modifications.

* (01/31/2006)--Modified S-register S37 to default to 5 and Direct Register 10 to default to 0x28 to improve modem connection rates.

* (01/27/2006)--Fixed a possible problem where setting the enable bit of Direct Register 1 of the SLIC could cause corruption of the PCM-law setting as well as other SLIC capabilities. If DR1 was read incorrectly before setting or clearing the PCM enable bit of DR1, then the PCM-law setting of DR1 could become corrupt and be written in the corrupted state to DR1. Setting/clearing the PCM enable bit happens when a POTS (voice/modem) call connects or disconnects, but if the corruption happened and the PCM-law setting was changed, then the POTS quality would greatly suffer and would not restore to correct settings until the TA was reset.

* (01/17/2006)--Fixed a bug in the flow control code where &E3 would not necessarily disable CTS/RTS flow control.

* (01/13/2006)--Added a condition to allow CLEAR sync mode to NOT use flow control (namely CTS/RTS) since in some circumstances RTS might cause erradic data or no data flow or possibly no synchronization. &E3 or &E5 will now disable CTS/RTS flow control for CLEAR sync mode.

* (12/16/2005)--Added code to debounce the on-hook/off-hook events for 20 ms before checking for a Tip/Ring ground short condition.

* (12/16/2005)--Fixed a bug with ATZ where %S1 would not get restored correctly and instead was restoring the top autobaud speed which typically is not the same as the top speed (baud rate).

* (12/16/2005)--Fixed a bug where if %S1 was stored then the TA would power up at the $SB speed and be fixed at that speed even if $SB was not the same as the top speed.

* (12/15/2005)--Added code to handle the ERROR vector.

* (12/01/2005)--Fixed a ringing voltage issue on the POTS port and modified the default value of S-register S39 to 59 V.

* (11/30/2005)--Fixed a problem where it was too easy to break out of fixed baud rate mode (%S1, %S2, or %S3) back to autobaud mode (%S0). Now the TA will only fall back to autobaud mode (%S0) if a break is detected on the serial port within 10 seconds after power-up while the TA is off-line and in command mode.

* (11/29/2005)--Fixed a problem with ATZ not restoring the correct %Sn setting. If %Sn was set for a fixed baud rate mode (%S1, %S2, or %S3) then it was not using the rate set by $SB or the top speed.

* (11/23/2005)--Fixed a buffer pointer bug for PPP/ML-PPP when converting packets from async to sync.

* (11/10/2005)--Added the capability to poll RTS while on-line just in case the TA misses a state transition interrupt for RTS.

* (10/25/2005)--Resolved a condition where the TA was ready to switch from UART mode to autobaud mode but right before the switch it received command data. This condition would cause a minimum 36-second delay until it would take AT commands again (depending on processor speed). Now the TA will remain in UART mode.

* (10/19/2005)--Removed timer for second UART (which doesn't exist) to free up processor cycles.

* (10/12/2005)--Added support for the software watchdog timer. However, if the TA locks up while servicing an interrupt of level 4 or higher then it will remain locked up.

* (10/10/2005)--Modified autobaud lookup table to match previous known good table (needed to add 1 to wMax in table).

* (09/01/2005)--Modified an exception handler that was being called while autobauding which would generate a fatal error. Now that exception is ignored even though it is not known why that exception was being generated.


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MTA128NT firmware release version 8.03
 Timestamp = 07-27-2005 10:03
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This is the initial release version that is specific to the Rev. E+
hardware. It does NOT function properly in the Rev. B-D MTA128NT.
ATI2 for this 8.xx firmware reports "MTA128NT-II" rather than
"MTA128NT" as was done for the 3.xx MTA128NT firmware. ATI20 reports
"MTA128NT-II" as well. 31.05 or newer boot code is required.


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* 2 **         Support Information        *
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Multi-Tech Systems has an excellent staff of technical support
personnel available to help you get the most out of your Multi-Tech
product. If you have any questions about the operation of this unit,
please call 800 972-2439 (USA and Canada) or 763 785-3500
(international and local). Please have modem information available.
You can also contact Technical Support by e-mail at the following
addresses:

Country          Email                       Telephone
France:          support@multitech.fr        +(33) 1-64 61 09 81
India:           support@multitechindia.com  +91 (124) 6340778
U.K.:            support@multitech.co.uk     +(44) 118 959 7774
U.S.A., Canada:  support@multitech.com       800 972-2439
Rest of world:   support@multitech.com       +763 717-5863


FTP Server:
  ftp://ftp.multitech.com

Web Site:
  http://www.multitech.com

US Mail Address:
  MultiTech Systems, Inc.
  2205 Woodale Drive
  Mounds View, MN 55112
  USA
