Retronetworking » Retro-GSM

h1. TCSM2 interchassis cable

The smallest functional TCSM2 system consists of one TC1C chassis and one ET1TC chassis; each chassis has its own backplane. A set of signals needs to be interconnected between the TRCO card in the TC1C chassis and the [[TCSM2_ET_modules|ET module]] in the ET1TC chassis - hence a special cable is needed that connects the two backplanes. On the back of each chassis there is a DIN 41612 connector (size C, 96 pins total) with male pins - the interchassis cable attaches to these two connectors, S00 on TC1C side and V00 on ET1TC side.

In a large system, each ET1TC chassis supports two TC1C chassis, hence whatever official cables Nokia once had (we haven't seen them) must have had a complex structure, with one half of V00 connector on ET1TC connected to one TC1C chassis and the other half connected to a different TC1C. However, if a hacker is putting together a minimal TCSM2 system in her lab and doesn't have Nokia's official cable, a simpler cable will need to be hand-crafted that connects the single TC1C to the single ET1TC.

Because the male DIN 41612 connectors on the exterior back faces of TC1C and ET1TC backplanes are of "full C" size, as opposed to "1/2 C" DIN 41612 connector on [[TCSM2_ET_modules|ET2E]], the availability of mating connector parts (female DIN 41612, free-hanging inline for mounting on cables) is a little better: several options are available from Digi-Key _without_ cost-prohibitive MOQ. For our setup in Themyscira lab, we are currently attempting to use "Harting 09032966823":https://www.digikey.com/en/products/detail/harting/09032966823/3179778 for the connector body and "Harting 09030960501":https://www.digikey.com/en/products/detail/harting/09030960501/3179722 for the shell housing. The parts are currently in shipping transit, hence no actual fit test has been performed yet.