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tuner_r820t: improve tuning accuracy, allow freq correction 

We now use Hz instead of KHz for calculating the PLL
parameters, and use the actual crystal frequency in Hz,
which allows to correct the frequency error in ppm.

Signed-off-by: Steve Markgraf <steve@steve-m.de>
This commit is contained in:
Steve Markgraf 2012-10-07 02:32:14 +02:00
parent 4c58bf8b1a
commit d64c969bd6
2 changed files with 37 additions and 22 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
include/tuner_r820t.h
View File

@ -130,6 +130,7 @@ typedef enum _R828_GPIO_Type
typedef struct _R828_Set_Info
{
UINT32 RF_Hz;
UINT32 RF_KHz;
R828_Standard_Type R828_Standard;
R828_LoopThrough_Type RT_Input;

58
src/tuner_r820t.c
View File

@ -20,7 +20,8 @@ int r820t_SetRfFreqHz(void *pTuner, unsigned long RfFreqHz)
// R828Info.R828_Standard = (R828_Standard_Type)pExtra->StandardMode;
R828Info.R828_Standard = (R828_Standard_Type)DVB_T_6M;
R828Info.RF_KHz = (UINT32)(RfFreqHz /1000);
R828Info.RF_Hz = (UINT32)(RfFreqHz);
R828Info.RF_KHz = (UINT32)(RfFreqHz/1000);
if(R828_SetFrequency(pTuner, R828Info, NORMAL_MODE) != RT_Success)
return FUNCTION_ERROR;
@ -981,11 +982,11 @@ R828_ErrCode R828_Init(void *pTuner)
if(R828_IMR_done_flag==FALSE)
{
#if 0
//write initial reg
if(R828_InitReg(pTuner) != RT_Success)
return RT_Fail;
#endif
// if(R828_InitReg(pTuner) != RT_Success)
// return RT_Fail;
//Do Xtal check
if((Rafael_Chip==R820T) || (Rafael_Chip==R828S) || (Rafael_Chip==R820C))
{
@ -1022,6 +1023,7 @@ R828_ErrCode R828_Init(void *pTuner)
R828_Fil_Cal_flag[i] = FALSE;
R828_Fil_Cal_code[i] = 0;
}
#if 0
//start imr cal.
if(R828_InitReg(pTuner) != RT_Success) //write initial reg before doing cal
@ -1266,7 +1268,7 @@ R828_ErrCode R828_IMR(void *pTuner, UINT8 IMR_MEM, int IM_Flag)
if(R828_MUX(pTuner, RingFreq - 5300) != RT_Success) //MUX input freq ~ RF_in Freq
return RT_Fail;
if(R828_PLL(pTuner, (RingFreq - 5300), STD_SIZE) != RT_Success) //set pll freq = ring freq - 6M
if(R828_PLL(pTuner, (RingFreq - 5300) * 1000, STD_SIZE) != RT_Success) //set pll freq = ring freq - 6M
return RT_Fail;
if(IM_Flag == TRUE)
@ -1331,9 +1333,9 @@ R828_ErrCode R828_PLL(void *pTuner, UINT32 LO_Freq, R828_Standard_Type R828_Stan
UINT8 Si;
UINT8 DivNum;
UINT8 Nint;
UINT32 VCO_Min;
UINT32 VCO_Max;
UINT32 VCO_Freq;
UINT32 VCO_Min_kHz;
UINT32 VCO_Max_kHz;
uint64_t VCO_Freq;
UINT32 PLL_Ref; //Max 24000 (kHz)
UINT32 VCO_Fra; //VCO contribution by SDM (kHz)
UINT16 Nsdm;
@ -1349,8 +1351,8 @@ R828_ErrCode R828_PLL(void *pTuner, UINT32 LO_Freq, R828_Standard_Type R828_Stan
Si = 0;
DivNum = 0;
Nint = 0;
VCO_Min = 1770000;
VCO_Max = VCO_Min*2;
VCO_Min_kHz = 1770000;
VCO_Max_kHz = VCO_Min_kHz*2;
VCO_Freq = 0;
PLL_Ref = 0; //Max 24000 (kHz)
VCO_Fra = 0; //VCO contribution by SDM (kHz)
@ -1361,6 +1363,7 @@ R828_ErrCode R828_PLL(void *pTuner, UINT32 LO_Freq, R828_Standard_Type R828_Stan
//UINT8 Judge = 0;
VCO_fine_tune = 0;
#if 0
if ((Rafael_Chip==R620D) || (Rafael_Chip==R828D) || (Rafael_Chip==R828)) //X'tal can't not exceed 20MHz for ATV
{
if(R828_Standard <= SECAM_L1) //ref set refdiv2, reffreq = Xtal/2 on ATV application
@ -1387,6 +1390,10 @@ R828_ErrCode R828_PLL(void *pTuner, UINT32 LO_Freq, R828_Standard_Type R828_Stan
PLL_Ref = R828_Xtal;
}
}
#endif
//FIXME hack
R828_Arry[11] &= 0xEF;
PLL_Ref = rtlsdr_get_tuner_clock(pTuner);
R828_I2C.RegAddr = 0x10;
R828_I2C.Data = R828_Arry[11];
@ -1410,14 +1417,14 @@ R828_ErrCode R828_PLL(void *pTuner, UINT32 LO_Freq, R828_Standard_Type R828_Stan
//Divider
while(MixDiv <= 64)
{
if(((LO_Freq * MixDiv) >= VCO_Min) && ((LO_Freq * MixDiv) < VCO_Max))
if((((LO_Freq/1000) * MixDiv) >= VCO_Min_kHz) && (((LO_Freq/1000) * MixDiv) < VCO_Max_kHz))
{
DivBuf = MixDiv;
while(DivBuf > 2)
{
DivBuf = DivBuf >> 1;
DivNum ++;
}
}
break;
}
MixDiv = MixDiv << 1;
@ -1442,9 +1449,14 @@ R828_ErrCode R828_PLL(void *pTuner, UINT32 LO_Freq, R828_Standard_Type R828_Stan
if(I2C_Write(pTuner, &R828_I2C) != RT_Success)
return RT_Fail;
VCO_Freq = LO_Freq * MixDiv;
VCO_Freq = (uint64_t)(LO_Freq * (uint64_t)MixDiv);
Nint = (UINT8) (VCO_Freq / 2 / PLL_Ref);
VCO_Fra = (UINT16) (VCO_Freq - 2 * PLL_Ref * Nint);
VCO_Fra = (UINT16) ((VCO_Freq - 2 * PLL_Ref * Nint) / 1000);
//FIXME hack
PLL_Ref /= 1000;
// printf("VCO_Freq = %lu, Nint= %u, VCO_Fra= %lu, LO_Freq= %u, MixDiv= %u\n", VCO_Freq, Nint, VCO_Fra, LO_Freq, MixDiv);
//boundary spur prevention
if (VCO_Fra < PLL_Ref/64) //2*PLL_Ref/128
@ -1530,12 +1542,14 @@ R828_ErrCode R828_PLL(void *pTuner, UINT32 LO_Freq, R828_Standard_Type R828_Stan
if( (R828_I2C_Len.Data[2] & 0x40) == 0x00 )
{
fprintf(stderr, "[R820T] PLL not locked!");
fprintf(stderr, "[R820T] PLL not locked for %u Hz!\n", LO_Freq);
R828_I2C.RegAddr = 0x12;
R828_Arry[13] = (R828_Arry[13] & 0x1F) | 0x60; //increase VCO current
R828_I2C.Data = R828_Arry[13];
if(I2C_Write(pTuner, &R828_I2C) != RT_Success)
return RT_Fail;
return RT_Fail;
}
//set pll autotune = 8kHz
@ -2518,7 +2532,7 @@ R828_ErrCode R828_Filt_Cal(void *pTuner, UINT32 Cal_Freq,BW_Type R828_BW)
return RT_Fail;
//Set PLL Freq = Filter Cali Freq
if(R828_PLL(pTuner, Cal_Freq, STD_SIZE) != RT_Success)
if(R828_PLL(pTuner, Cal_Freq * 1000, STD_SIZE) != RT_Success)
return RT_Fail;
//Start Trigger
@ -2552,7 +2566,7 @@ R828_ErrCode R828_Filt_Cal(void *pTuner, UINT32 Cal_Freq,BW_Type R828_BW)
R828_ErrCode R828_SetFrequency(void *pTuner, R828_Set_Info R828_INFO, R828_SetFreq_Type R828_SetFreqMode)
{
UINT32 LO_KHz;
UINT32 LO_Hz;
#if 0
// Check Input Frequency Range
@ -2563,16 +2577,16 @@ R828_ErrCode R828_SetFrequency(void *pTuner, R828_Set_Info R828_INFO, R828_SetFr
#endif
if(R828_INFO.R828_Standard==SECAM_L1)
LO_KHz = R828_INFO.RF_KHz - Sys_Info1.IF_KHz;
LO_Hz = R828_INFO.RF_Hz - (Sys_Info1.IF_KHz * 1000);
else
LO_KHz = R828_INFO.RF_KHz + Sys_Info1.IF_KHz;
LO_Hz = R828_INFO.RF_Hz + (Sys_Info1.IF_KHz * 1000);
//Set MUX dependent var. Must do before PLL( )
if(R828_MUX(pTuner, LO_KHz) != RT_Success)
if(R828_MUX(pTuner, LO_Hz/1000) != RT_Success)
return RT_Fail;
//Set PLL
if(R828_PLL(pTuner, LO_KHz, R828_INFO.R828_Standard) != RT_Success)
if(R828_PLL(pTuner, LO_Hz, R828_INFO.R828_Standard) != RT_Success)
return RT_Fail;
R828_IMR_point_num = Freq_Info1.IMR_MEM;