We have bought several xbee series 1 modules: XB24-AWI-001 to be more precise.
As far as I know, these modules consists of a MC9S08GT60 micro-controller and a Freescale MC13193 RF chip.
Using a recent firmware, the instruction set provides a command (PL) to set the power level at which the module transmits (from -10dbm to 0dbm).
I found out that the MC13193 RF Chip transmission power can be programmed to even lower levels (i.e. -27dbm), which is precisely what we want.
Therefore, if the last premise is true, there must be a way to modify / create a firmware that allows the module to transmit at this power level (-27dbm). Maybe a patch to the firmware files may do the job.
Any advise on this?
We offer none. However, the manual shoudl explain which pins of the CPU connect to which pins of the XBee module. The maker of the chip MIGHT offer some free code for it.
I will guess that you are trying to use the Xbee as a ‘location’ detector, so want a very low signal to enable the XBee to ‘lose’ the old connection when for example it leaves a room.
The problem with this is the XBee by design tries to keep an old connection as long as possible, so even if there are 3 ‘better’ connections it will try to stick to the last now ‘bad’ one. To do ‘location’ detection like this, you really need your own CPU and code to constantly scan for other ‘access points’ and use some value to select the best one.
