Copper SFP

Here you can ask technical questions about REVELPROG-IS and device/memory programming.
LarsRoe
Posts: 1
Joined: Sat Feb 06, 2021 5:48 pm

Copper SFP

Postby LarsRoe » Mon Feb 08, 2021 7:59 am

Hello and good morning

I'm currently trying to load the attached file into an OEM SFP. This is what we apparently made. The switch shows me this type, but unfortunately it doesn't work. No data is received. When I plug in the original it works perfectly. I also get no error message that a password is set. Do I have to pay attention to anything else? I've tried one with other SFP always the same. :cry:

Larsen
Attachments
MAster.bin
(256 Bytes) Downloaded 137 times

ArT
Posts: 1377
Joined: Wed Mar 25, 2015 8:54 am
Location: Warsaw, Poland
Has thanked: 48 times
Been thanked: 143 times

Re: Copper SFP

Postby ArT » Mon Feb 08, 2021 10:45 am

Hi Lars, when you program SFP with your dump, does verification pass? If yes, write success and sfp is not write protected. I'm not SFP compatibility expert but did you recalculated cheksums before write? (there is checksum button). Without corret checksum it may not work. The other reason may be that this firmware you are trying to upload is not compatible with your SFP type or with your switch.

User avatar
neogator
Posts: 3
Joined: Mon Jan 10, 2022 12:00 am
Location: UA
Contact:

Re: Copper SFP

Postby neogator » Mon Jan 10, 2022 10:59 pm

Copper modules do not support A2h page. It is useless to try to guess a password or use a known password for such a module, because the password input field does not exist. An attempt to write a password to such a module will not return any errors.
Serial ID data is stitched into the EEPROM of the transceiver at the factory. The 24C02 series EEPROM chip has a special WP - Write Protect pin designed to control the write protection function. When WP pin is connected to Vcc power plan, write protect function is enabled.
The WP pin of the EEPROM is usually connected to the SFP port pins, which by default are in a high logic level and do not change their state during normal operation.

User avatar
neogator
Posts: 3
Joined: Mon Jan 10, 2022 12:00 am
Location: UA
Contact:

Re: Copper SFP

Postby neogator » Tue Jan 11, 2022 8:52 pm

Typically, OEM copper SFPs are based on a simple EEPROM such as the 24C02 and do not have a PCB-mounted MCU that performs write protection function in accordance with SFF 8472.
Often the WP pin is connected to one of the TX or RX power circuits of the transceiver. This trick is used by the manufacturer since the copper modules do not have a laser and an optical receiver.
Your task is to try to break the power lines of the transceiver in turn and try to write to the module every time.
Also TX_DISABLE which is connected to Vcc in normal state is often used to control write protection.
Further blocking options are possible using the TX_FAULT line, it is also useless for a copper transceiver and can be used in vendor special functions to control write protection. In contrast to the above, a logical unit must be sent to the TX_FAULT line.
All of the same is true for DAC cables.
Try all 4 options)


Return to “Technical Support”

Who is online

Users browsing this forum: No registered users and 1 guest

cron