Problems receiving what I thought were four HEX bytes?

[Jerson]

Is there a way you can confirm the baud rate the device is seeing? One way to check could be to send some command that does something verifiable on the module like flashing some led or something. This way you can confirm that the device is indeed operating at the correct baud rate. Then comes the return information check. Are you able to see simple things like maybe a AT OK coming from the module? If not, is it possible you might be seeing inverted data?

These are some thoughts that come to mind

[jellis00]

I am confident that the baud rate is not a problem. Otherwise none of the commands I am sending to the module would result in the results I am seeing posted on the web site.
Yes, I am seeing the OK returns on the commands, so I don't think that is a problem.
Just the fact that my command to send the array sereial_no[ ] ends up with the same value posted on the web site that I am reading back from EEPROM tells me that the commands are getting through.

However, I don't understand what you mean by "inverted data"....can you please explain?

[Jerson]

Ok, my doubts about baud rate are clarified. Inverted data means I was thinking you are seeing the complement of the data due to the RxD line not being inverted by a line driver IC.