// pats TODO: Send the transceiver an idle frame rather than doing it here.
// There is one of these for each timeslot, ie, for ccch_group.
void CCCHLogicalChannel::ccchServiceLoop()
{
// build the idle frame
static const L3PagingRequestType1 filler;
static const L3Frame idleFrame(filler,L3_UNIT_DATA);
bool isCCCHCombined = gControlChannelDescription->isCCCHCombined();
// TODO: Send idle frame to transceiver.
// Calculate maximum number of frames of delay.
// See GSM 04.08 3.3.1.1.2 for the logic here.
static const unsigned txInteger = gConfig.getNum("GSM.RACH.TxInteger");
assert(txInteger <= 15);
// RACH slot definition: we see in GSM 5.02 clause 7 table 3 of 9 that a RACH can appear on timeslots 0,2,4, or 6, and in table 5 of 9 we
// see that for a non-combined CCCH-CONF any of the 51 frames can be used, and for combined CCCH-CONF the available (51*4=204 slots/51-multiframe)
// frames are: B4, B5, B14, B15 ... B36, B45, B46 (27*4=108 slots/51-multiframe.)
// GSM 4.08 11.1.1, And I quote: "The minimum value of this timer is equal to the time taken by T+2S slots of the mobile station's
// RACH. S and T are defined in sub-clause 3.3.1.2. The maximum value of this timer is 5 seconds."
static const int stval = GSM::RACHSpreadSlots[txInteger] + 2*(isCCCHCombined ? GSM::RACHWaitSParamCombined[txInteger] : GSM::RACHWaitSParam[txInteger]);
// Subtract some frames from the maxAge to make sure we still have time left to send it; the amount should be 4 frames
// plus some time for the MS to receive and decode it plus the slack induced by the OpenBTS tranceiver interface, which we do not know.
sMaxAge = min(stval, (int)(5 * 51 * 4.2)) - 6;
for (int i = 0; i < 51; i++) {
mRevPCH[i] = -1; // -1 means not used for paging.
}
mRevPCH[16] = 0;
int cnt = 0;
while (! gBTS.btsShutdown()) {
if (! ccchServiceQueue()) {
// Nothing to send on CCCH frame, so just send an idle frame.
//LOG(DEBUG)<<"sending page as idleframe";
l2sendf(idleFrame);
}
}
if (cnt); // shut up gcc.
}
void CBCHLogicalChannel::l2sendm(const L3SMSCBMessage& msg)
{
L3Frame frame(L3_UNIT_DATA,88*8);
msg.write(frame);
l2sendf(frame);
}
// Serialize and send an L3Message with a given primitive.
// The msg is not deleted; its value is used before return.
void L2LogicalChannelBase::l2sendm(const L3Message& msg, GSM::Primitive prim, SAPI_t SAPI)
{
//OBJLOG(INFO) << "L3" <<LOGVAR(SAPI) << " sending " << msg;
WATCHINFO("l2sendm "<<this <<LOGVAR(SAPI) << " sending " << msg);
l2sendf(L3Frame(msg,prim,SAPI));
}
