Minicom Connection Over Serial Port To PIC18F452 Device

[Robert L Cochran]

Peter Arremann wrote:

>On Thursday 06 April 2006 19:04, 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.
>>
>>Serial device -- /dev/TTYS0 connected to development board Max232 chip
>>
>>setup for 19200 bps,8N1, software flow control, VT102 emulation
>>
>>iptables service is stopped
>>
>>When I connect, the setup program appears. It is just a menu with 8
>>choices. In fact, the setup menu sometimes displays itself twice.
>>
>>I select an option say 2 to set the IP address. The device very
>>sensibily responds with the default ip address. I type in a new IP
>>address to reflect my actual network.
>>
>>If I try to select 2 to check the default IP address, it again sensibly
>>responds with the new IP address that I just gave it. So far, so good.
>>
>>Then I select the option to save the new IP address. a message is
>>returned which is usually the new IP address itself.
>>
>>Attempts to ping that IP address fail.
>>
>>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.
>>
>>Thanks
>>
>>Bob Cochran
>>    
>>
>
>
>Is the IP address stored in an eeprom or a battery buffered ram? If the answer 
>is eeprom, check your power supply. You need 2 different voltages to read and 
>write to an eeprom. So its possible that on startup the firmware copies the 
>IP into ram - that's where you modify it. It is actually not written back to 
>the prom, so the next time you power on, you go back to the default IP... 
>
>I doubt it has anything to do with minicom unless the display issue keeps you 
>from seeing a "save" menu entry that you'd have to execute... 
>
>Peter.
>
>  
>
Thank you -- yes there is an EEPROM, it is the Microchip 24LC256. I 
reinspected it and pin 1 doesn't look quite right. Maybe I should try to 
reflow the other pins too.

I'm not sure where the IP address is stored, but I do know a *.bin file 
containing the web pages has to be loaded into the EEPROM.

I made a typo above -- the ethernet controller is the RTL8019AS.

The PIC18F452 chip just dropped out of its socket. I hope I haven't 
wrecked it.

Thanks

Bob