Problems with a serial device

Hi all,

I have a device that works linked to the serial port of a PC. Throw this serial port some commands are sent to return some information. I am trying to do a circuit that allows me, after of send a command throw the serial port, desconect the device from the PC maintening the suply by a baterry, and store autonomly ina temporal memory all sent by the device for, later, plug it to the PC and download the info stored in this temporal memory. I do not know if I have explained myself correctly but I have been trying to do this assembly for a long time and I have test some things that do not respond correctly. If someone have done something similar or knows where could I find this info or someone that could give me it, I will thank a lot any help.

Thank you in advance

Something like this?

do

lot

You don't say what the problem is.

When you reconnect the device do you flush the buffers in the serial port at both ends?

This "serial device test utility" is quite useful if you want to send packets of data with headers and footers and monitor what comes back.