B. Related Circuit of Program Updating
The related circuit of program is shown as Figure 3. The
data transmission of the DSP and DM9000A is used 16-bit
mode. The EES pin of the DM9000A keeps the default
floating state and the data lines SD0~SD15 directly connect
to the TMS320VC5402 low data lines D0~D15.
TMS320VC5402’s R/W line is send to CPLD to generate
logical signal, then connect to IOR and IOW of the
DM9000A. The CS pin of DM9000A is control by CPLD
logical signal which generated by DSP_IOS and A15 of
TMS320VC5402[6]. So the network controller I/O port
address (IOaddress) is 0x8000. The address lines AD of
TMS320VC5402 by CPLD connect to CMD pin, so two
external port address of DM9000 are:
INDEX port address =0x8000+0x00;
DATA port address =0x8000+0x01