Minicom Connection Over Serial Port To PIC18F452 Device

[Robert L Cochran]

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