Sundance SMT410 v.1.0 - Manual (Page 16)

Page 16 of 49 SMT410 User Manual V1.0
D7 D6 D5 D4 D3 D2 D1 D0
X X CENc CENb SELC SELB SEL1 SEL0
Table 5 : ComPort configuration register
The table below illustrates the different setting of the register.
CENc CENb SEL1 SEL0 Function
1 X X X Connects DSP ComPort 3 to PCI Host
1
0 X X X Disconnects DSP ComPort 3 to PCI Host
X 0 X X Disables all DSP connections to Buffered ComPort
X 1 0 0 Connect DSP ComPort 0 to Buffered ComPort
2
X 1 0 1 Connect DSP ComPort 2 to Buffered ComPort
2
X 1 1 0 Connect DSP ComPort 3 to Buffered ComPort
2
X 1 1 1 Connect DSP ComPort 5 to Buffered ComPort
2
Table 6 : Comport selection
1
If SELC is read as 0 then CENc is overridden as DSP ComPort 3 is now being driven by the
external FMS connector J2.
2
If SELB is read as 0 then CENb is overridden as buffered ComPort is now connected to
external FMS connector J1.
BUF_COM_DIR : Selects the direction of the buffered ComPort = SEL1
7.1 Buffered ComPort
From the TIM site, 4 ComPorts are taken to a back panel mounted connector via
quick switches. All signals are pulled up to +3.3 volts with 330 ohm resistors. The
active devices are mounted as close as possible to the connector they serve.
The back panel mounted connector is a 26 pin 3M type, (3M part number 10226-
5212JL). The connector pin-out is given in the following table, with pair numbers for
13 off twisted pair cable (3M part number KUCKMPVVSB28-13PAIR).
The buffer circuit for the connector is designed such that the reset direction is defined
by the TIM ComPort number to which it is connected. The quick switch arrangement
allows cable less connection between the TIM site and the buffer. There is also a 14-
way surface-mount FMS connector allowing the buffer to be connected to some
external source of data. When this connector is used, all other quick switch TIM site
connections are removed.