SB6121 and SB6141 modems.

SB6XXX,SBV6XXX

Moderators: justsomeguy, Koevoet

Post Reply
usbbdm
Junior Member
Posts: 8962
Joined: Mon Jul 18, 2005 9:33 pm

SB6121 and SB6141 modems.

Post by usbbdm »

Today I have received two modems by member here who failed to read and program those modems.

Even though there are a lot of information on how to do this already, but most of them used the method that apply 5V on pin 2 of flash. I am not big fan of this and would always try to find ISP pin if possible.

The SB6121 and SB6141 are very similar in hardware design. The SB6121 that came with the box was dead due to the soldering. I was not able to read the flash on the board (some pads are damaged). I managed to read back the flash by removing it from the PCB and connect directly to NT. 3.3v to HOLD and VCC. TRST to WP. The rest connections are the same as it with SB6120.

The SB6141 is fully functional and the ISP pin was found on pin2 of U7. If you connect Pin 1 of USB JTAG NT to pin 2 of U7 (I added additional 100 ohm between to add extra protection). This works exactly like the ISP mode for SB6120.

For tester who would like to program often, make connection like this
viewtopic.php?t=4106
and you do not need any extra 3.3v or 5V. Just connect USB JTAG NT and you are ready to go.

I will soon make a webpage about this ISP method for SB6121/6141 modems. For the past few months, those questions have been asked many times and now we have a final solution.
uga
Junior Member
Posts: 45
Joined: Sat Sep 19, 2009 8:28 pm
Location: usa

Post by uga »

Thanks for the information..............
Pir8pete
Junior Member
Posts: 105
Joined: Thu Nov 02, 2006 5:56 pm
Location: C A N A D A

Post by Pir8pete »

I should have packed it better, box must have been stacked, had some weight on it when shipping. Oh well, now I'll have to install some new pads and re-attach it to the trace.
My main focus is the SB6141 as it does 8x4, might scrap the SB6121 in July when my ISP has there new package.

Do you think 100 ohm is needed between pin1 of the USBJTAG to the ISP points?

Confirmed ISP points?;
-SB6121 ISP point = R153 right side
-SB6141 ISP point = pin2 on U7
usbbdm
Junior Member
Posts: 8962
Joined: Mon Jul 18, 2005 9:33 pm

Post by usbbdm »

Pir8pete wrote:I should have packed it better, box must have been stacked, had some weight on it when shipping. Oh well, now I'll have to install some new pads and re-attach it to the trace.
My main focus is the SB6141 as it does 8x4, might scrap the SB6121 in July when my ISP has there new package.

Do you think 100 ohm is needed between pin1 of the USBJTAG to the ISP points?

Confirmed ISP points?;
-SB6121 ISP point = R153 right side
-SB6141 ISP point = pin2 on U7
I used it and it works. Someone had used 2K and works. It is better to add some protection than nothing.
marthypaul
Junior Member
Posts: 133
Joined: Fri Dec 12, 2008 3:30 pm

Post by marthypaul »

What is U7, found it finally. It is kind of power regulator.
Still do not know, which is pin2, checked with data sheet, kind of confusing.
They number it differently. There is already resistor on pin "2", so maybee there is o need for extra resistor.
But this regulator gives power up to 18V.
usbbdm
Junior Member
Posts: 8962
Joined: Mon Jul 18, 2005 9:33 pm

Post by usbbdm »

Today I used 3.3v direct to the SB6120 flash and I am able to read/write SPI flash properly. I think most people would like this method. Seems quite simple.
joejoe332006
Junior Member
Posts: 166
Joined: Sat Aug 02, 2008 6:40 pm
Location: USA

Post by joejoe332006 »

usbbdm wrote:Today I used 3.3v direct to the SB6120 flash and I am able to read/write SPI flash properly. I think most people would like this method. Seems quite simple.
External 3.3Volts is always a better choice. I have done that since day 1.lol
Post Reply

Who is online

Users browsing this forum: Google [Bot] and 3 guests