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Writing to Protected SFP ?
Posted: Tue Jul 11, 2017 5:01 pm
by sisgene
Hi,
Just got a RevelProg + SFP Adapter. Reading many SFP brands fine.
Testing writing to OEM SFP, OK.
Trying to write to Finisar SFP always fail, tried 3 differents ref.
Googling around and found some manufacturer implements a kind of Password protection.
Someone have clues to write to theses "protected" SFP with RevelProg ?
Thanks.
Pierre
Re: Writing to Protected SFP ?
Posted: Tue Jul 11, 2017 10:16 pm
by ArT
edit note 2020-01-27:
since v1.8.2 update you can use password tool for password entry or password hacking, please check it:viewtopic.php?f=31&t=527-------------------------------------------------------------------
You can use
custom script tool to write password to eeprom and unlock the SFP but you need to know (1) what addresses should be modified and (2) what is the password - it may be impossible to get this information if you do not have close friend in Finisar... (I do not have such information

). They describe in datasheets only password for user eeprom area (page 27
https://cdn.hackaday.io/files/215999240 ... eivers.pdf) but this is MSA standard and any word about manufacturer password. If you find any information please let me know.
I had the same problem with Finisar (and others) XFP modules (we are working on XFP adapter). There is the same situation - vendor area is write protected and I can't find information how to unlock it (not only me - it is popular issue on other forums...)
Re: Writing to Protected SFP ?
Posted: Wed Jul 12, 2017 10:04 am
by sisgene
Hi Art,
This is a bad new ... I did'nt check enough.
The goal of the prog+adapter is to work with Finisar SFP.
So, some guys, by exemple, at S F P Tot al, have "secret" infos (and scripts) to deal with table A0 on Finisar or it's fake ?
Could you give script exemple how to "write" a 4 bytes password to A2, adr 7B as it's the reference for SFP ? (seems FC is also a good start)
It's for understanding the script.
Lately a batch mode have to be found, to write PSW values in A2 and test Write/read in A0.
Pierre.
Re: Writing to Protected SFP ?
Posted: Thu Jul 13, 2017 8:39 am
by ArT
As I know you can only read and write to user area but can not erase and write to manufacturer area for finisar (that's why these modules are so cheap on aftermarket).
I wrote you example script, first is pw write 4 byte at once, second is byte by byte (some SFP may require first method, some second). You can make script with GUI from script maker in application.
Code: Select all
// SFP 4 byte password write to 0x7B (4 byte at once: 0x11, 0x22, 0x33, 0x44)
#SCRIPT HEADER;
SCRIPT:v1.6.1;
#HARDWARE SETTINGS;
HW:I2C,3.0V,SLOW;
// write 4 byte password to 0x7B (10ms delay after write)
#OPERATION;
SW:1,3,0,0,0,0,10,0,0,500;
INSTR:A2,7B;
DATA:11,22,33,44;
Code: Select all
// SFP 4 byte password write to 0x7B (byte by byte: 0x11, 0x22, 0x33, 0x44)
#SCRIPT HEADER;
SCRIPT:v1.6.1;
#HARDWARE SETTINGS;
HW:I2C,3.0V,SLOW;
// write 1 byte password to 0x7B (10ms delay after write)
#OPERATION;
SW:1,0,0,0,0,0,10,0,0,500;
INSTR:A2,7B;
DATA:11;
// write 1 byte password to 0x7C (10ms delay after write)
#OPERATION;
SW:1,0,0,0,0,0,10,0,0,500;
INSTR:A2,7C;
DATA:22;
// write 1 byte password to 0x7D (10ms delay after write)
#OPERATION;
SW:1,0,0,0,0,0,10,0,0,500;
INSTR:A2,7D;
DATA:33;
// write 1 byte password to 0x7E (10ms delay after write)
#OPERATION;
SW:1,0,0,0,0,0,10,0,0,500;
INSTR:A2,7E;
DATA:44;
Please note that in some SFP you can write password only directly after SFP power up (it may not work after any operation), so you may need to unplug and plug SFP if you did any operation before.
Re: Writing to Protected SFP ?
Posted: Thu Jul 13, 2017 3:50 pm
by sisgene
Ok, Thanks. I'll try.