From 26c50b42789b671f0483f1de6c2ec2b5fbb7afde Mon Sep 17 00:00:00 2001 From: c vw Date: Tue, 4 Aug 2020 16:05:46 +0200 Subject: [PATCH] HermesLite2 PS feedback update --- old_protocol.c | 40 ++++++++++++++++++++++++++++++++-------- 1 file changed, 32 insertions(+), 8 deletions(-) diff --git a/old_protocol.c b/old_protocol.c index ffabfb8..dc03359 100644 --- a/old_protocol.c +++ b/old_protocol.c @@ -1465,11 +1465,24 @@ static int last_power=0; // encode all 6 bits of RXgain in ATT value and set bit6 if (isTransmitting()) { // - // Set the preamp to (19-TXatt) dB (+19 ... –12 dB) - // temporary change: use more amplification to allow PURESIGNAL on - // a barefoot HL2 with "cross talk" feedback from the TRX relay + // The "TX attenuation" value (0 ... 31 dB) has to be mapped to a + // a range of preamp settings. This range is very different on the + // HermesLite when using "internal" feedback (crosstalk from the + // RX/TX releay) or "external" feedback (attenuator output + // connected with RF3 input of the HermesLite2). + // To cope with both situations, the preamp range is + // +2 ... +33 dB if "Internal" feedback is selected in the + // PS menu (this is optimal for "crosstalk" feedback) and + // if external feedback is used (check either EXT1 or ByPass + // in the PS menu) the preamp range is -12 ... +19 dB. // - output_buffer[C4] = 0x40 | (45 - (transmitter->attenuation & 0x1F)); + // + output_buffer[C4] = 0x40 | (33 - (transmitter->attenuation & 0x1F)); +#ifdef PURESIGNAL + if (receiver[PS_RX_FEEDBACK]->alex_antenna == 0) { + output_buffer[C4] = 0x40 | (45 - (transmitter->attenuation & 0x1F)); + } +#endif } else { output_buffer[C4] = 0x40 | (rxgain & 0x3F); } @@ -1525,10 +1538,21 @@ static int last_power=0; output_buffer[C1]|=(receiver[1]->adc<<(2*rx2channel)); } } - output_buffer[C3]=0x00; - // this is a no-op on the HermesLite2 which needs b7 set to make this effective - // no need to bother here since we do this manually (see above) - output_buffer[C3]|=transmitter->attenuation & 0x1F; // Step attenuator of first ADC, value used when TXing + if (have_rx_gain) { + // + // On the HermesLite2, we need bit7 set to make this feature active, + // and need bit6 set to tell HL2 to directly use the lowest 6 bits + // for the built-in preamp. For the effect of choosing different + // "alex antennas" see above. + output_buffer[C3] = 0xC0 | (33 - (transmitter->attenuation & 0x1F)); +#ifdef PURESIGNAL + if (receiver[PS_RX_FEEDBACK]->alex_antenna == 0) { + output_buffer[C3] = 0xC0 | (45 - (transmitter->attenuation & 0x1F)); + } +#endif + } else { + output_buffer[C3]=transmitter->attenuation & 0x1F; // Step attenuator of first ADC, value used when TXing + } output_buffer[C4]=0x00; break; case 7: -- 2.45.2