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Part 2: Ethernet-Equipped
RabbitCore Modules
by Fred Eady
Start
• The Networking Core
• Code Names and Comedy
• Where and Why • Completing
Initialization Down
to Business • Now What?
• Sources and PDF
NOW WHAT?
The next step is up
to the application. If TCP/IP communications are
to be established, the socket services of Dynamic
C Premier use the RTL8019AS you just initialized
to pass packets over an Ethernet or the Internet.
Photo 2 is a STDIO window shot of what happened
after I ran the sock_init function following
the hardware init process I just described.
You’ll see some values that will be familiar to
you. The Boundary and Page Start values are set
at 0x46, just where the code put them. Page Stop
is registering 0x60. Our bogus ’9346 read put 0x30
in the RTL8019AS LED control register CONFIG3. Although
you never really saw the MAC address, it’s sitting
pretty in the PARX registers and judging by the
identical values in the CURR and BNRY registers,
I caught this register listing before any packets
were received.
| Photo
2—This window was generated using a function
in the Realtek Dynamic C Premier library called
prt_nicreg. I simply inserted the function
call before a call to sock_init. The
prt_nicreg function is handy for those
of you who don’t have access to a Sniffer.
You can insert this call anywhere you wish
to examine the contents of the RTL8019AS registers. |
I’ve written lots of
articles describing Z-World and Rabbit Semiconductor
hardware. The idea behind this walk through microcode
land was to show you how you too can use the resources
of the Dynamic C Premier source code to your advantage.
I essentially took nothing but C and assembler source
code from various Dynamic C Premier libraries and
pieced together the functionality of the RTL8019AS
Ethernet IC. You used the Rabbit Semiconductor web
site to view schematic drawings of the RCM2100 and
technical updates relating to the hardware and software
while reading this column. The open-source attitude
that Z-World and Rabbit Semiconductor apply to their
product lines makes products like the RCM2100 ideal
learning tools.
I’m out of virtual
paper. Next time I’ll show you some tricky hardware
solutions based on the new Ethernet-based RabbitCore
line.
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