Black Box High Speed COS-4, Руководство пользователя

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CHAPTER 4: Installation
Table 4-1. Pinning, AT Computer to COS (EVMBMC Cable*)
Computer COS as DCE
DB9 DB25
RD 2 ----------------------------------- 3 TD
TD 3 ----------------------------------- 2 RD
DTR† 4 ----------------------------------- 20 DTR†
SGND 5 ----------------------------------- 7 SGND
CTS† 8 ----------------------------------- 5 CTS†
Table 4-2. Pinning, PC/XT Computer or Serial Printer to COS
(ECM12C Cable**)
Computer COS as DCE
DB25 DB25
TD 2 ----------------------------------- 2 RD
RD 3 ----------------------------------- 3 TD
CTS† 5 ----------------------------------- 5 CTS†
SGND 7 ----------------------------------- 7 SGND
DTR† 20 ----------------------------------- 20 DTR†
*Our EVNBMC cable is pinned this way. It also carries the other pins supported by
the AT serial interface, but the High Speed COS-4 and COS-8 don’t support any of
the other pins except Pin 1, PGND, which is not required.
†When a device attached to the COS raises its flow-control lead, the COS sends the
appropriate flow-control signal to the device on the other end of the connection. For
example, suppose an administrator PC on Port 0 is communicating with a user PC on
Port 4. Both PCs are DTEs, so both ports are set as DCE. When the PC on Port 0
raises DTR, the COS raises CTS on Port 4; and when the PC on Port 4 raises DTR,
the COS raises CTS on Port 0. On the other hand, if the device on Port 4 is a mux (a
DCE, so that Port 4 is set as DTE), then when the PC on Port 0 raises DTR, the COS
raises DTR on Port 4; and when the mux on Port 4 raises CTS, the COS raises CTS
on Port 0.
**Our ECM12C cable is pinnned this way. It also carries Pin 1, PGND, which the High
Speed COS-4 and COS-8 support but doesn’t require, as well as Pins 4, 6, 8, 15, 17,
and 22 (RTS, DSR, RLSD [DCD], TSETC [TC], RSET [RC], and RI respectively),
which the COSes don’t support at all.