Werner Almesberger writes: >Joe Pfeiffer wrote: >> I'm confused -- do you mean there is no way to turn off the modem's RF >> amp? What do other phones using it do to comply with airplane >> regulations? > >The RF amplifier has an input called TX_ENABLE, which is connected to >TSPACT09 of the GSM baseband processor, so the GSM chipset can tell it >whether to transmit or not.
So, in your previous post >That [EMAIL PROTECTED] doesn't cut power to the modem. Instead, it tells the >modem to "power down", i.e., to enter its own standby mode, from >which it can be awakened by "pressing" the modem's "on" button. >(That "button" is in fact a transistor controlled by MODEM_ON line >which connect to the CPU's GPB7.) Are you drawing a distinction between 'turning the modem off' vs. telling the transmitter not to transmit? In the context of airplane rules, the latter ought to be just as good...
