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11. SB4100/SB4200 using a MAX232/MAX233 serial cable


The following screen shots and text were put together by,




These are the solder points for the SB4100 & SB4200 where you'll need to connect your serial cable. Also if you're using a Max 232 from Tailor Made Circuits you'll need to connect to the modem as follows,

1 = Tx = Red

2 = Rx = Yellow

3 = Vcc = Blue

4 = GND = Black


11a. SB4100


11b. SB4100 - Rev a


11c. SB4101


11d. SB4200


11e. SB5100


Now once you've connected your interface cable:


1) Start by going to:

Start ' Control Panel ' Network Connections


2) Right click local area connection and click properties.

(If you have more then one, make sure that you select the one your modem is connected to)


3) Click on "Internet protocol (TCP/IP)" once (do not uncheck it), & click properties, now set it up like this:


NOTE: You will need to have your Ethernet cable attached.



4) Now open the program called Boot.exe


5) Open HyperTerminal or Terraterm and set your baud settings to: 38400


6) Connect your serial cable to your modem interface and power up your modem


7) Type: 2 & press Enter, this will allow you to boot over Ethernet.

You should now see something like this:




8) Once Boot.exe has finished running reboot your modem and go to and you should now see this page:





11 * How to: add diagnostic serial output to a SB5100

By Jubal of surfboard hackers



The SB5100 modem has all the pads on the board to allow the (fairly) easy addition of diagnostic serial output. It only requires the addition of one chip, four capacitors and one connector.

It's a pretty quick project and then you'll be able to see what the modem is doing in a bit more detail than normal.

Before we start, though, please read this:



Big Scary Warning:

This project involves surface mount soldering. Surface mount soldering takes skill, patience, and a proper set of tools. If you don't take time to learn surface mount soldering on a spare board, you may damage or destroy your modem. Don't come crying to us if you break your modem!


Okay, lets have a look at the board for a moment.


You can see above the blank spot on the board that we're going to populate.

U12 is a MAX3221CUE

C131, C150, C151, C152 are all 1uf capacitors.

J4 is where we connect up a serial port connection.


(we've not been able to figure out which is the exact part that goes in the area of J4. updates are welcome!)


Max3221CUE can be ordered in sample quantities directly from the manufacturer:

The capacitors are generic 0805 case 1uf parts


The first step is to mount the MAX3221 on the board.

You're going to need:

A pair of surface mount tweezers.

A Good soldering station.

A very fine point tip.

A heat gun with a narrow nozzle

A bottle of soldering flux, and some very fine solder.




Daub a bit of soldering flux over the areas that you will be soldering. The flux will allow the solder to flow as the iron heats the parts.

Position the chip carefully on the board. Take note of the orientation of pin 1 (the dot), and make very certain that the pins are lined up with the board. Make certain again.




There are a couple ways to solder the chip in place.

One method is to use the tweezers to hold the chip in position and use the heat gun to heat the pins and board at the same time. The flux will boil, the solder on the board will melt and the pins will sink into place.

The other method is to use the tweezers to hold the chip in place, and to wipe the fine tip of the soldering iron across the pins, longways. This will have the same result as above.

Either technique will work. When done, go back and check your work for solder bridges and mis-aligned pins.

Hopefully you have neither of these.




You can see that the chip slipped very slightly as I was soldering it, but all the joins are good and there are no solder bridges.


Next, we will attach the capacitors.

You'll need four.

Use the tweezers to grab a capacitor. I have found it is easiest to hold the capacitor in the middle, between the two solder points.

Postition the capacitor on the board, and use the fine tip soldering iron to heat one side and melt it in place. Then heat the other side, pressing down on the capacitor. Alternate heating and pressing sides until the capacitor is flush with the board. (I usually go back and forth 3 times.)

Repeat this process with the other three capacitors.



Almost there!

The next step is to attach a connector to the board.

The original board uses a 1/8" stereo jack, but we weren't able to figure out which exact part to order - so for the moment I've just temporarily soldered a 9-pin male jack into place.



In the picture to the Right


The Red wire is pin 2 of the DB-9 (transmit data).

The Orange wire is pin 3 of the DB-9 (recieve data).

The Green wire is pin 5 of the DB-9 (ground).

Its likely that your connector will use different colors than mine.

Once you've soldered everything together, connect the RS-232 to your computer, and using your favorite terminal program select the

com port,

8 bits,

no parity, one stop bit

115200 bits per second.

take a deep breath, and plug the power to your modem in.


If you've done it properly, here is what you will see:





Good luck!


Heres picture with jack in places..







11** Change Firmware Via Serial Board on 5100


Tut by daks001

Surfboard hacker




1. Open up your local area connection properties and change your network card to;






2. Ensure that your firewall is not blocking tftp or port 69.

3. Start up tftp32 and ensure the firmware file is in it's (root directory)

4. Go into the COnsole on your modem and type in;

cd /doc


dload firmware.bin

(firmware.bin = your firmware filename)


if you have a ST flash chip on your modem you should use the command



dload -i1 firmware.bin



If you are using "non-signed" firmware for the modem the command will change to;



dload -f firmware.bin



IF you want to upgrade your bootloader now issue the following commands;


cd /ip



bootloader -f bootloader.bin

(bootloader.bin=your bootloader filename)


(Yes it goes very quick compared to the Jtag)