The mlxcables tool supports reading cable data directly via i2c when the cable is connected to a dedicated board. The board is connected to the host with an MTUSB adapter.
Examples on a Windows machine:
After adding the cables using 'mst cable add' the following mst status is presented:
mst status MST devices: ------------ mtusb-1 Cable MST devices: ------------------- mtusb-1_cable
Query the cable:
mlxcables -d mtusb-1_cable Querying Cables .... Cable #1: --------- Cable name : mtusb-1_cable FW version : 2.0.208 FW Dev ID : 0x20 FW GW version : Legacy -------- Cable EEPROM -------- Identifier : QSFP+ (0dh) Technology : 850 nm VCSEL (00h) Compliance : 40G Active Cable (XLPPI), 100G AOC (Active Optical Cable) or 25GAUI C2M AOC. Wavelength : 850 nm OUI : 0x0002c9 Vendor : Mellanox Serial number : MT1707FT01544 Part number : MFA1A00-E001 Revision : A1 Temperature : 31 C Length : 1 m
Read from a specific address:
mlxcables -d mtusb-1_cable -r -p 0 -o 165 -l 3 Page[0].Byte[165] = 0x00 Page[0].Byte[166] = 0x02 Page[0].Byte[167] = 0xc9
