Photo 2. Using the
the Easy Ethernet Controller, you'll need a good terminal emulation program for your PC. The best of them
is free and it's called Tera Term Pro. You can download
Tera Term Pro from their site on the Internet and from
many of the shareware and freeware download sites.
I suggest using Tera Term Pro 32 for Windows
NT/2000 and the standard 16-bit Tera Term Pro if
you're running Win98. Hyper Terminal will work as well
but Tera Term Pro actually displays the download
progress whereas Hyper Terminal looks dead while the
download process is running. Another plus for Tera
Term Pro is that is can be "programmed" using a built-in scripting language to automate its operation.
After the Ethernet module is tied into the
PIC16F877's I/O, there are still enough PIC I/O pins
left over to use for things like analog input and digital
The pins that interface to I2C devices are also
clear, allowing you to add such things as temperature
sensors, real-time clocks, EEPROM, LED and LCD controllers, and additional I/O ports, just to name a few.
The PIC pins SA0-SA4 are used to address the
RTL8019AS's internal registers and can do double
duty when they aren't talking to the RTL8019AS IC.
For instance, Microchip sells a demo board that
uses these pins to access a standard LCD module
when they are not addressing the RTL8019AS.
So, even though it looks like the PIC16F877 is
"used up" by the Ethernet module, there are plenty of
PIC I/O opportunities that can still be exploited once
the Ethernet module is installed and running. I added
a single LED on PORTA to demonstrate basic I/O
NUTS & VOLTS
Schematic 2. Connections
to the Realtek chip.