Sundance SMT364 - Manual (Page 12)

Version 1.0 Page 12 of 37 SMT364 User Manual
TTL I/Os.
Four TTL I/Os (J4 – see Figure 8 - Connector Location.) are connected directly to the
FPGA. They support LVTTL signals. It is recommended to make sure the lines
connected to these pins are LVTTL compatible in order not to damage the FPGA
pads, as lines are not clamped.
Sundance Standards.
Communication Ports (ComPorts).
According to the board you can get up to six 8-bit, data-parallel, inter-processor links
that follow Texas Instruments’ TMS320C4x Communication Port standard. Additional
information on the standard is available in the TMS320C4x User’s Guide chapter 12:
Communication ports and the Texas Instrument Module Specification .
The standard gives a TIM six links numbered from 0 to 5. Each link can be a
transmitter or a receiver, and will switch automatically between these states
depending on the way you use it. Writing to a receiver or reading from a transmitter
will cause a hardware negotiation (token exchange) that will reverse the state of both
ends of the link.
Following a processor reset, the first three links (0, 1, and 2) initialise as transmitters
and the remainder (3, 4, and 5) initialise as receivers. When you wire TIMs together
you must make sure that you only ever connect links initialising as transmitters to
links initialising as receivers; never connect two transmitters or two receivers. For
example, connecting link 0 of one TIM to link 4 of another is safe; connecting link 0 of
one TIM to link 2 of another could damage the hardware.
Always connect ComPort 0, 1 or 2 to ComPort 3, 4 or 5.
On most carrier board the physical connection between ComPorts is made with FMS
cables (Ref. SMT3xx-FMS). You must be careful when connecting the cables the
make sure that one end is inserted in the opposite sense to the other. One end must
have the blue backing facing out and the other must have the silver backing facing
out.
The SMT310Q (SMT320) motherboard communicates with the host PC using
ComPort 3 of the site 1 TIM. You should not make any other connections to this
ComPort.
ComPorts (Communication ports) links follow Texas Instrument C4x standard. They
are 8-bit parallel inter-processor ports of the ‘C4x processors.
The ComPorts drive at 3.3v signal levels.
The FPGA can implement up to two FIFO buffered ComPort interfaces fully compliant
with the TIM standard. They are guaranteed for a transfer rate of 20MB/s.
The FIFOs are useful to maintain a maximum bandwidth and to enable parallel
transfers.