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tuner_r820t: add manual RF gain setting 

Signed-off-by: Steve Markgraf <steve@steve-m.de>
This commit is contained in:
Steve Markgraf 2012-10-19 01:17:28 +02:00
parent aabd42dd05
commit 25789493c6
3 changed files with 77 additions and 24 deletions
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3
include/tuner_r820t.h
View File

@ -172,7 +172,8 @@ R828_ErrCode R828_GPIO(void *pTuner, R828_GPIO_Type R828_GPIO_Conrl);
R828_ErrCode R828_SetStandard(void *pTuner, R828_Standard_Type RT_Standard);
R828_ErrCode R828_SetFrequency(void *pTuner, R828_Set_Info R828_INFO, R828_SetFreq_Type R828_SetFreqMode);
R828_ErrCode R828_GetRfGain(void *pTuner, R828_RF_Gain_Info *pR828_rf_gain);
R828_ErrCode R828_RfGainMode(void *pTuner, R828_RF_Gain_TYPE R828_RfGainType);
R828_ErrCode R828_SetRfGain(void *pTuner, int gain);
R828_ErrCode R828_RfGainMode(void *pTuner, int manual);
int
r820t_SetRfFreqHz(

9
src/librtlsdr.c
View File

@ -180,8 +180,8 @@ int r820t_init(void *dev) {
int r820t_exit(void *dev) { return 0; }
int r820t_set_freq(void *dev, uint32_t freq) { return r820t_SetRfFreqHz(dev, freq); }
int r820t_set_bw(void *dev, int bw) { return 0; }
int r820t_set_gain(void *dev, int gain) { return 0; }
int r820t_set_gain_mode(void *dev, int manual) { return 0; }
int r820t_set_gain(void *dev, int gain) { return R828_SetRfGain(dev, gain); }
int r820t_set_gain_mode(void *dev, int manual) { return R828_RfGainMode(dev, manual); }
/* definition order must match enum rtlsdr_tuner */
static rtlsdr_tuner_iface_t tuners[] = {
@ -788,7 +788,10 @@ int rtlsdr_get_tuner_gains(rtlsdr_dev_t *dev, int *gains)
63, 65, 67, 68, 70, 71, 179, 181, 182,
184, 186, 188, 191, 197 };
const int fc2580_gains[] = { 0 /* no gain values */ };
const int r820t_gains[] = { 0 /* no gain values */ };
const int r820t_gains[] = { 0, 9, 14, 27, 37, 77, 87, 125, 144, 157,
166, 197, 207, 229, 254, 280, 297, 328,
338, 364, 372, 386, 402, 421, 434, 439,
445, 480, 496 };
const int unknown_gains[] = { 0 /* no gain values */ };
int *ptr = NULL;

89
src/tuner_r820t.c
View File

@ -2929,7 +2929,60 @@ R828_ErrCode R828_GetRfGain(void *pTuner, R828_RF_Gain_Info *pR828_rf_gain)
return RT_Success;
}
R828_ErrCode R828_RfGainMode(void *pTuner, R828_RF_Gain_TYPE R828_RfGainType)
/* measured with a Racal 6103E GSM test set at 928 MHz with -60 dBm
* input power, for raw results see:
* http://steve-m.de/projects/rtl-sdr/gain_measurement/r820t/
*/
#define VGA_BASE_GAIN -47
static const int r820t_vga_gain_steps[] = {
0, 26, 26, 30, 42, 35, 24, 13, 14, 32, 36, 34, 35, 37, 35, 36
};
static const int r820t_lna_gain_steps[] = {
0, 9, 13, 40, 38, 13, 31, 22, 26, 31, 26, 14, 19, 5, 35, 13
};
static const int r820t_mixer_gain_steps[] = {
0, 5, 10, 10, 19, 9, 10, 25, 17, 10, 8, 16, 13, 6, 3, -8
};
R828_ErrCode R828_SetRfGain(void *pTuner, int gain)
{
int i, total_gain = 0;
uint8_t mix_index = 0, lna_index = 0;
for (i = 0; i < 15; i++) {
if (total_gain >= gain)
break;
total_gain += r820t_lna_gain_steps[++lna_index];
if (total_gain >= gain)
break;
total_gain += r820t_mixer_gain_steps[++mix_index];
}
/* set LNA gain */
R828_I2C.RegAddr = 0x05;
R828_Arry[0] = (R828_Arry[0] & 0xF0) | lna_index;
R828_I2C.Data = R828_Arry[0];
if(I2C_Write(pTuner, &R828_I2C) != RT_Success)
return RT_Fail;
/* set Mixer gain */
R828_I2C.RegAddr = 0x07;
R828_Arry[2] = (R828_Arry[2] & 0xF0) | mix_index;
R828_I2C.Data = R828_Arry[2];
if(I2C_Write(pTuner, &R828_I2C) != RT_Success)
return RT_Fail;
return RT_Success;
}
R828_ErrCode R828_RfGainMode(void *pTuner, int manual)
{
UINT8 MixerGain;
UINT8 LnaGain;
@ -2937,8 +2990,7 @@ R828_ErrCode R828_RfGainMode(void *pTuner, R828_RF_Gain_TYPE R828_RfGainType)
MixerGain = 0;
LnaGain = 0;
if(R828_RfGainType==RF_MANUAL)
{
if (manual) {
//LNA auto off
R828_I2C.RegAddr = 0x05;
R828_Arry[0] = R828_Arry[0] | 0x10;
@ -2958,25 +3010,15 @@ R828_ErrCode R828_RfGainMode(void *pTuner, R828_RF_Gain_TYPE R828_RfGainType)
if(I2C_Read_Len(pTuner, &R828_I2C_Len) != RT_Success)
return RT_Fail;
MixerGain = (R828_I2C_Len.Data[3] & 0xF0) >> 4;
LnaGain = R828_I2C_Len.Data[3] & 0x0F;
/* set fixed VGA gain for now (16.3 dB) */
R828_I2C.RegAddr = 0x0C;
R828_Arry[7] = (R828_Arry[7] & 0x60) | 0x08;
R828_I2C.Data = R828_Arry[7];
if(I2C_Write(pTuner, &R828_I2C) != RT_Success)
return RT_Fail;
//set LNA gain
R828_I2C.RegAddr = 0x05;
R828_Arry[0] = (R828_Arry[0] & 0xF0) | LnaGain;
R828_I2C.Data = R828_Arry[0];
if(I2C_Write(pTuner, &R828_I2C) != RT_Success)
return RT_Fail;
//set Mixer gain
R828_I2C.RegAddr = 0x07;
R828_Arry[2] = (R828_Arry[2] & 0xF0) | MixerGain;
R828_I2C.Data = R828_Arry[2];
if(I2C_Write(pTuner, &R828_I2C) != RT_Success)
return RT_Fail;
}
else
{
} else {
//LNA
R828_I2C.RegAddr = 0x05;
R828_Arry[0] = R828_Arry[0] & 0xEF;
@ -2990,6 +3032,13 @@ R828_ErrCode R828_RfGainMode(void *pTuner, R828_RF_Gain_TYPE R828_RfGainType)
R828_I2C.Data = R828_Arry[2];
if(I2C_Write(pTuner, &R828_I2C) != RT_Success)
return RT_Fail;
/* set fixed VGA gain for now (26.5 dB) */
R828_I2C.RegAddr = 0x0C;
R828_Arry[7] = (R828_Arry[7] & 0x60) | 0x0B;
R828_I2C.Data = R828_Arry[7];
if(I2C_Write(pTuner, &R828_I2C) != RT_Success)
return RT_Fail;
}
return RT_Success;