Robert L Cochran wrote:
Mike McCarty wrote:
Robert L Cochran wrote:
I'm trying to use minicom on Fedora Core 4 to speak to a PIC18F452
chip which contains a preloaded version of the Microchip TCP/IP
stack. I built the device myself from a kit; it is intended to be a
small web server. My objective is to assign an IP address to the
RTL9019AS ethernet controller. This can be accomplished over a setup
menu that appears in the minicom window. I suspect I have incorrect
minicom settings.
[snip]
Then I start the setup menu again in a new minicom window. The
original -- default -- IP address appears.
So it seems like the option to save the IP address isn't working
right. Things are apparently lost when I restart the device.
Is this a minicom software issue, or is it bad soldering on my part
with the actual device being tested? I'm quite willing to agree it
may have soldering issues.
I don't see how it can be Minicom. All it does is transport
characters from your keyboard out the serial port, and from
the serial port to your display. If you are getting communications
with the device, then Minicom is doing its job. Without knowing
more about the PIC device, I can't say any more. Are you using
shadow RAM or nonvolatile RAM or EEPROM or FLASH EEPROM or what
to store? If it uses a RAM copy, but saves config in a serial
EEPROM, it could be that you indeed have a solder problem
on the board, like a cold solder joint to the data clock pin.
In any case, I don't see how it can be Minicom.
Mike
Thank you -- I will check my soldering work; I've already looked at
the EEPROM (a Microchip 24LC256) and I think I did a poor job on pin
1. Probably the other pins too, this is the first SOIC I've ever
soldered.
I also think I need to learn about the different types of RAM and
EEPROM you are referencing above. I know i'm using an EEPROM, but I
need to learn what shadow or nonvolatile RAM is and how an EEPROM
differs from a flah EEPROM.
I'll start looking at datasheets and do some resoldering.
Thanks
Bob
My thanks to Peter, Mikkel and Mike for their help with this. I was able
to get the board working in its web server capacity. Here is what fixed it:
I resoldered the 24LC256 EEPROM chip. That allowed the IP address
changes to "stick". It also allowed me to upload the website image to
the EEPROM.
I noticed that the device was plugged into a 100 Mbps-only network hub.
The Reaktek RTL8019AS is a 10 Mbps chip. Changing to a 10/100 Mbps wired
router and creating a second, smaller network was the finishing touch.
Suddenly, I can access the Microchip demonstration website stored on the
24LC256 chip.
Now to learn how to actually program a PIC microcontroller.
Bob
