You can't "assign" your chip reader to sda1 or to any device, it's the driver job to do so.
What are the last few lines of "dmesg" when you plug it? There should be lines saying something like "New usb device found at X" at the very least, otherwise there is something wrong about your kernel (no usb support?).
Here is a sample, from my system, this is what I get when I plug my flash drive :
Initializing USB Mass Storage driver...
usb.c: registered new driver usb-storage
scsi0 : SCSI emulation for USB Mass Storage devices
Vendor: Sony Model: Sony DSC Rev: 3.22
Type: Direct-Access ANSI SCSI revision: 02
WARNING: USB Mass Storage data integrity not assured
USB Mass Storage device found at 2
USB Mass Storage support registered.
Attached scsi removable disk sda at scsi0, channel 0, id 0, lun 0
SCSI device sda: 126848 512-byte hdwr sectors (65 MB)
sda: Write Protect is off
If you see something like the following, then it is possible that the usb-storage driver is missing from your system or it is not activated yet :
hub.c: USB new device connect on bus1/1, assigned device number 2
usb.c: USB device 2 is not claimed by any active driver. (The 0x54c/0x10 will be different for different vendors.)
In that case, try to "modprobe usb-storage" then see dmesg again.