Unable to directly connect WTI CMS-16 to a SG200-26 switch

Question

Hello,
We recently replaced a Netgear 16-port JGS516 gigabit switch with a Cisco SG200-26 switch.  When we did, we lost our ability to talk to our WTI CMS-16 (Western Telematics 16-port serial lines).   The CMS-16 has a 10Base-T Ethernet, RJ45 connector that provides telnet access to 16 serial ports.
When we put a Netgear DS104 hub in between the CMS-16 and the SG200-26, all is well.  Packets flow back and forth and we are able to ping and telnet to the CMS-16 through the hub.
When we directly connect the CMS-16 to the SG200-26 and ping the CMS-16, the "Status & Statistics"->Interface records transmitted packets and "nil" received packets. By "nil" we mean that if we wait long enough the statistics reports an occasional (about once every few minutes) 68-octet Unicast packet was received.
When the CMS-16 is directly connected, the SG200-26 link light is lit. We cannot Administration->Diagnostics->"Copper Test" because the "Copper Test" button is greyed out.
When the CMS-16 is plugged into the Netgear DS104 hub, the CMS-16 port has its 10M LED lit, and the port connected to the SG200-26 has its 100M LED lit.
Our SG200-26 switch is running firmware version 1.1.0.73.   We are using a single LVAN ... nothing fancy.  The CMS-16 is running firmware version 2.06.
Do we need to configure the port on the SG200-26 in some special way to deal with this legacy CMS-16 device?
chongo (Landon Curt Noll) /\oo/\

Answer 1

Hello Dave,
We tried your idea by making the following change on the SG200-26:
Administration -> Port Management -> Port Settings -> 7 -> ((Click Edit))
    ((unplug the cms-16 from Port 7))
    Interface: GE7
    Port Description: cms-16
    Administrative Status: (*) Up
    Reactivate Suspected Port: [x]
    Auto Negoation: [ ] Enable
    Administrative Port Speed: (*) 10M
    Administrative Duplex Mode: (*) Half
    MDI/MDIX: (*) Auto
    ((Click Apply))
    ((Plug in ithe cms-16 to Port 7))
Unfortunately that did not fix the problem.  Namely:
When we directly connect the CMS-16 to the SG200-26 and ping the CMS-16, the "Status & Statistics"->Interface records transmitted packets and "nil" received packets. By "nil" we mean that if we wait long enough the statistics reports an occasional (about once every few minutes) 68-octet Unicast packet was received. We cannot Administration->Diagnostics->"Copper Test" because the "Copper Test" button is greyed out.
When we put a Netgear DS104 Dual-Speed "hub" in between the CMS-16 and the SG200-26, all is well.  Packets flow back and forth and we are able to ping and telnet to the CMS-16 through the hub.  Now both the CMS-16 port and the port connected to the SG200-26 has both of their 10M LEDs lit.  (i.e., the above configuration change DID force the port to operate at 10M).
Are there other parametes we need to change on the SG200-26?
Thanks for your help.
chongo (Landon Curt Noll) /\oo/\
p.s. We have two Network Power Switches, also by the same manufacturer (WTI) and of the same "vintage" (c. 2000) that operate just fine at 10M and Half Duplex.