in the C5509 system. When a structure is
protocol. Opting for a serial interface in-
This system uses a software-based serial
overlaid on this data buffer for parsing,
stead of Ethernet allows ARP support code
the members of the structure do not con-
and the ARP table to be removed. Not us-
tain the correct data values. Because of
ing UDP can also reduce the code size.
this difference, the main structure for the
These options are easily removed, via
TCP/IP header, uip_tcpip_hdr (located in
macros, in the uIP stack.
the uip.h file), must be modified. Fur-
“One of the major
The flow of incoming packets can be
thermore, the code that uses this structure
throttled by adjusting the maximum seg-
must also be modified.
differences between
ment size of incoming data allowed by the
Listing One(a) is the original uip_
sensor node. Other system optimizations
tcpip_hdr header structure. Structure
that are ideal for wireless sensor networks
the C5509 and most
members that are of type u8_t do not
are available, but require more in-depth
need to be modified, because the only
configuration. Areas for further investiga-
processors is the
difference on the C5509 platform is that
tion include TCP/IP header compression
these types will occupy 16 bits of memo-
techniques to reduce overhead of the var-
ry each instead of the typical 8 bits. How-
treatment of the
ious protocol headers. This is best for sen-
ever, the u16_t type members do need to
sor systems comprised of nodes that typ-
be changed. Listing One(b) is the modi-
char type”
ically transmit smaller data packets.
fied structure to accommodate the C5509-
For TCP, packet retransmission schemes
based prototype board.
are available that move the resending of
Next, these structure changes are in-
lost packets closer to the destination of
corporated into the uIP networking code.
the data rather than relying on the source
port for network connectivity. Some host
An example of code using the new struc-
point. This can also reduce the length that
configuration is necessary in order to set
ture is in uip.c, where the TCP source and
an acknowledgement needs to travel
up the host PC to communicate using SLIP
destination port numbers are swapped to
through the system.
over the serial port.
format the header of an outgoing packet.
The uIP stack includes an example SLIP
Listing Two(a) is the original code, and
Porting the uIP Stack to the
driver, which we modified to accommo-
Listing Two(b) the modified code. Other
TMS320C5509 DSP
date the radio sensor board hardware. The
variables that pose the same issue between
To further examine the uIP stack, we
original SLIP driver polls the serial port
the C5509 platform and a standard pro-
built a prototype wireless radio sensor
for incoming data and stores each char-
cessor are also modified in a similar way.
board that was based on the TMS-
acter, applying the SLIP data translation
In this example, BUF is a uip_tcpip_hdr
320C5509 digital-signal processor from
changes where necessary, as it arrives.
pointer type and points to the start of the
Texas Instruments. For most ports of the
The sensor board code uses an interrupt
incoming network packet. Because we
uIP stack, the TCP/IP code doesn’t need
for serial port, allowing the ISR to store
changed the original srcport from a 16-bit
to be modified. However, unique features
the incoming data. When a complete net-
unsigned short into an array of two 16-bit
of the TMS320C5509 DSP made it neces-
work packet is received, a flag is set to
unsigned short elements, we need to store
sary for us to change uIP core files. Fig-
start the processing of the data.
the srcport array elements properly. This
ure 4 illustrates the uIP directory struc-
One of the major differences between
example also shows the destport code
ture. A new architecture-specific directory,
the C5509 and most processors is the treat-
modification.
ment of the char type. On the C5509, a
These modifications are done through-
char is 16 bits rather than 8 bits, as found
out the uIP source code. Another file that
on typical processors. This adds some
needs attention is uip_arch.c, which is lo-
challenges to porting the uIP code that is
cated in the architecture-specific directo-
designed to accommodate an 8-bit char
ry. This file contains the TCP and IP check-
type. In the C5509 world, a char, short, sum routines.
and int are all at 16 bits and data space
After porting the uIP networking code
memory is addressed 16 bits at a time.
to the C5509, the main processing loop is
uip-0.9 - main directory for uIP stack version 0.9
(a)
apps - application modules
httpd - web server module
Address Data


 

 

 

 

 

 

 

 

 

 

 

 

   
 
  char type) would look similar to Figure able, such as the Serial Line Interface stacks; this is an add-on module that is 5(a), while Figure 5(b) shows the...
Pomodliłem się do każdego boga jaki istniał bym był w wstanie wkurzyć tę kobietę do granic możliwości.