In this firmware that is ARM Little endian.
There is two strings :
0x00006953 : Foretrex 701 0x00006960 : Foretrex 601
The issue, is there is no direct Xreft to any of thoses strings ?
For the firmware, it's pretty much the same.
As IDA cannot find the entry point, to start analyzing the binary (after setting CPU to arm little endian) select all the code (with CTRL+SHIFT+PAGE_DOWN) press C, then "Analyze"