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+How to configure modem support in U-Boot :
+
+1. Define modem initialization strings:
+---------------------------------------
+
+The modem initialization strings have following format:
+
+	mdm_init1=<AT-command>
+	mdm_init2=<AT-command>
+	...
+
+Turning off modem verbose responses with ATV0 or ATQ1 is not allowed;
+U-Boot analyzes only verbose (not numeric) result codes. Modem local
+command echo can be turned off (ATE0).
+
+2. RTS/CTS hardware flow control:
+---------------------------------
+
+You may wish to enable RTS/CTS hardware flow control, if the board's
+UART driver supports it (see CONFIG_HWFLOW compile-time flag in
+config/<board>.h). This is controlled by the 'mdm_flow_control'
+environment variable:
+
+	'mdm_flow_control=rts/cts'  - to enable RTS/CTS flow control.
+	'mdm_flow_control=none '    - to disable.
+
+
+The following are the examples using a Rockwell OEM modem
+configuration:
+
+SAMSUNG # setenv mdm_init1 ATZ			- reset the modem to
+						  the factory defaults.
+SAMSUNG # setenv mdm_init2 ATS0=1               - set modem into
+						  answer mode.
+SAMSUNG # setenv mdm_flow_control rts/cts       - enable serial port
+						  flow control
+SAMSUNG # saveenv
+
+The example above initializes modem into answer mode to wait for the
+incoming call. RTS/CTS flow control is enabled for the serial port.
+(The RTS/CTS flow control is enabled by default on the modem).
+
+
+SAMSUNG # setenv mdm_init1 ATZ
+SAMSUNG # setenv mdm_init2 ATS39=0+IFC=0,0	- disable modem
+						  RTS/CTS flow control
+SAMSUNG # setenv mdm_init3 ATDT1643973         -  dial out the number
+SAMSUNG # setenv mdm_flow_control none
+SAMSUNG # saveenv
+
+The example above initializes modem to dial-up connection on the
+number 1643973. Flow control is disabled.
+
+Note that flow control must be turned both off or both on for the
+board serial port and for the modem.
+
+
+If the connection was set up successfully, the U-Boot prompt appears
+on the terminal console. If not (U-Boot modem was configured for
+originating the call and connection was not established) - the board
+should be reset for another dial-up try.
+
+
+Note on the SMDK2400 board:
+---------------------------
+
+Since the board serial ports does not have DTR signal wired, modem
+should be told to ignore port DTR setting prior to connection to the
+SMDK board, and this setting should be stored in modem NVRAM. For the
+Rockwell OEM modem this can to be done with the following command:
+
+AT&D0&W