Sundance SMT358 - Manual (Page 12)

Version 2.5 Page 12 of 25 SMT358 User Manual
Alternatively, the Sundance Digital Bus links can be extended to external
interconnection by connecting them to the SMT373 mezzanine card.
With this card, TTL signals are converted to Low-Voltage Differential signals and can
connect two systems several meters apart.
It provides two bi-directional 20-bit channels that can transfer up to 2 Gbytes/s through forty
SN65LVDM176 transceivers. Each channel provides 16 bit of data, a clock and a clock-
enable signal with their direction controlled by one signal. Two other signals can be used for
the bus arbitration in a bi-directional application. The direction of each of them can be
controlled independently.
All the signals controlling the direction are connected to the SMT358 FPGA through the
connectors and so can be controlled by software.
SMT358-DSP Communication channels
The global bus or Comm-Port 0,1,3 or 4 are communication channels of the SMT358 used to
interfaced to T.I.’s DSP processors.
The ‘C4x Protocol defines Byte-wide links which can theoretically transmit at
20MBytes/second asynchronously between TIMs.
The Global Bus is only available when the SMT358 is connected onto the SMT350PB mother
board.
The SMT350PB provides a non-blocking global bus interconnection between any source TIM
site and any other destination TIM site. It provides a sustainable throughput of 50 MBytes/s
between any of the module sites even with three modules accessing the same destination
module. Access to the PCI bus takes place through TIM site 1. Please see our Web Site at
http://www.sundance.com/
Figure 5 shows the various dedicated DSP communication channels available on the SMT358
for inter-TIM data transfers.