Thanks all for continuing this discussion, all good stuff.
I'll include the reg list here if you don't mind, just in case the file goes away on Drae's server.
By the way, if someone has nice results or wants to share another driver (maybe Drae with the TCP/IP-ish approach?) and is willing to do a writeup, I would be more than happy to post it on the blog.
const byte CONFIG[][2] =
{
/* 0x01 */ { REG_OPMODE, RF_OPMODE_SEQUENCER_ON | RF_OPMODE_LISTEN_OFF | RF_OPMODE_STANDBY },
/* 0x02 */ { REG_DATAMODUL, RF_DATAMODUL_DATAMODE_PACKET | RF_DATAMODUL_MODULATIONTYPE_FSK | RF_DATAMODUL_MODULATIONSHAPING_00 }, //gaussian, bt=1.0
/* 0x03 */ { REG_BITRATEMSB, RF_BITRATEMSB_38400}, //default:4.8 KBPS
/* 0x04 */ { REG_BITRATELSB, RF_BITRATELSB_38400},
/* 0x05 */ { REG_FDEVMSB, RF_FDEVMSB_50000}, //default:5khz, (FDEV + BitRate/2 <= 500Khz)
/* 0x06 */ { REG_FDEVLSB, RF_FDEVLSB_50000},
/* 0x07 */ { REG_FRFMSB, (freqBand==RF69_315MHZ ? RF_FRFMSB_315 : (freqBand==RF69_433MHZ ? RF_FRFMSB_433 : (freqBand==RF69_868MHZ ? RF_FRFMSB_869 : RF_FRFMSB_915))) },
/* 0x08 */ { REG_FRFMID, (freqBand==RF69_315MHZ ? RF_FRFMID_315 : (freqBand==RF69_433MHZ ? RF_FRFMID_433 : (freqBand==RF69_868MHZ ? RF_FRFMID_869 : RF_FRFMID_915))) },
/* 0x09 */ { REG_FRFLSB, (freqBand==RF69_315MHZ ? RF_FRFLSB_315 : (freqBand==RF69_433MHZ ? RF_FRFLSB_433 : (freqBand==RF69_868MHZ ? RF_FRFLSB_869 : RF_FRFLSB_915))) },
// looks like PA1 and PA2 are not implemented on RFM69W, hence the max output power is 13dBm
// +17dBm and +20dBm are possible on RFM69HW
// +13dBm formula: Pout=-18+OutputPower (with PA0 or PA1**)
// +17dBm formula: Pout=-14+OutputPower (with PA1 and PA2)**
// +20dBm formula: Pout=-11+OutputPower (with PA1 and PA2)** and high power PA settings (section 3.3.7 in datasheet)
///* 0x11 */ { REG_PALEVEL, RF_PALEVEL_PA0_ON | RF_PALEVEL_PA1_OFF | RF_PALEVEL_PA2_OFF | RF_PALEVEL_OUTPUTPOWER_11111},
///* 0x13 */ { REG_OCP, RF_OCP_ON | RF_OCP_TRIM_95 }, //over current protection (default is 95mA)
// RXBW defaults are {RF_RXBW_DCCFREQ_010 | RF_RXBW_MANT_24 | RF_RXBW_EXP_5} (RxBw: 10.4khz)
/* 0x19 */ { REG_RXBW, RF_RXBW_DCCFREQ_010 | RF_RXBW_MANT_16 | RF_RXBW_EXP_2 }, //(BitRate < 2 * RxBw)
/* 0x25 */ { REG_DIOMAPPING1, RF_DIOMAPPING1_DIO0_01 }, //DIO0 is the only IRQ we're using
/* 0x29 */ { REG_RSSITHRESH, 220 }, //must be set to dBm = (-Sensitivity / 2) - default is 0xE4=228 so -114dBm
///* 0x2d */ { REG_PREAMBLELSB, RF_PREAMBLESIZE_LSB_VALUE } // default 3 preamble bytes 0xAAAAAA
/* 0x2e */ { REG_SYNCCONFIG, RF_SYNC_ON | RF_SYNC_FIFOFILL_AUTO | RF_SYNC_SIZE_2 | RF_SYNC_TOL_0 },
/* 0x2f */ { REG_SYNCVALUE1, 0x2D }, //attempt to make this compatible with sync1 byte of RFM12B lib
/* 0x30 */ { REG_SYNCVALUE2, networkID }, //NETWORK ID
/* 0x37 */ { REG_PACKETCONFIG1, RF_PACKET1_FORMAT_FIXED | RF_PACKET1_DCFREE_OFF | RF_PACKET1_CRC_ON | RF_PACKET1_CRCAUTOCLEAR_ON | RF_PACKET1_ADRSFILTERING_OFF },
/* 0x38 */ { REG_PAYLOADLENGTH, MAX_DATA_LEN }, //in variable length mode: the max frame size, not used in TX
//* 0x39 */ { REG_NODEADRS, nodeID }, //turned off because we're not using address filtering
/* 0x3C */ { REG_FIFOTHRESH, RF_FIFOTHRESH_TXSTART_FIFONOTEMPTY | RF_FIFOTHRESH_VALUE }, //TX on FIFO not empty
/* 0x3d */ { REG_PACKETCONFIG2, RF_PACKET2_RXRESTARTDELAY_2BITS | RF_PACKET2_AUTORXRESTART_ON | RF_PACKET2_AES_OFF }, //RXRESTARTDELAY must match transmitter PA ramp-down time (bitrate dependent)
/* 0x6F */ { REG_TESTDAGC, RF_DAGC_CONTINUOUS }, // run DAGC continuously in RX mode
{255, 0}
};