Sundance SMT335 - Manual (Page 14)

Version 3.0 Page 14 of 34 SMT335 User Manual
Interrupts
See general firmware description
Communication ports
The SMT335 provides six comm-ports.
See general firmware description
Data rates
When using the communication links of a C6000 you must remember that the links
share a single bus, so the performance you get will depend on the way you sequence
bus accesses.
C6201 can read at 100MHz from external to internal memory; the rate for the C6701
is 83MHz. If you want to store in external memory then the rate achievable are
divided by two as the read and writes share the same bus, which means respectively
50MHz and 41MHz.
The C6000 DMA channels are not efficient when moving data between two external
memory areas sharing a common bus; the transfer will take place a word at a time
and not in more efficient bursts. This is why it may not be advisable to use DMA to
transfer data directly between external memory and a communication link.
Performance can be greatly improved by using an intermediate buffer in internal
memory.
SDB
The SMT335 provides two Sundance Digital Buses (SDBs).
See general firmware description
SDB update
You should be aware that revisions of the SDB before V3.0.6 have a significantly
different treatment of the status flags and a different address is used to program the
SDB flag levels for input and output. When upgrading from versions before V3.0.6,
you will need to change the code for flag programming and accessing the status bits.
You should use version V3.3.6 or above because previous versions could generate
spurious interrupts on input.
SDB Clock selection
At any time you can change the speed of an SDB clock by altering SDBCLK.