Sundance SMT317 - Manual (Page 9)

Version 6.1 Page 9 of 24 SMT317 User Manual
7. Communication ports
7.1. Overview
The SMT317 communication port is an 8-bit, data-parallel, link that follows 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 comm-ports 0, 1, or 2 to comm-ports 3, 4, or 5.
On the SMT320-SMT310Q carrier board the physical connection between
comm-ports is made with FMS cables. You must be careful when connecting
the cables and 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 SMT320 SMT310Q motherboard communicates with the host PC using comm-
port 3 of the site 1 TIM. You should not make any other connections to this comm-
port.
On the SMT317
• Comm-port 3 is used for the FPGA configuration. It is the only way to
configure the FPGA.
• Comm-port 3 is used for both configuring the FPGA and afterwards for
controlling the ADCs data acquisition. In that configuration you save one
connection in your system.
• Nevertheless, if your application requires using a different Comm-port to
control the acquisition, (the FPGA configuration can only be done via
Comm-port3) please contact Sundance as a custom version of the firmware
with more Comm-port connections could be developed for you.
• The control comm-port selection is achieved by setting
• JMP1: Control Comm-port Select. The standard version of the firmware only
provides Comm-port 3.