Vergil_Wong/lib_xua
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Reduce control loop rate to 100Hz

Browse Source
This commit is contained in:
Ed
2024-01-05 11:18:29 +00:00
parent 702e8d14b9
commit b242c54574
1 changed files with 26 additions and 14 deletions
Download Patch File Download Diff File Expand all files Collapse all files

40
lib_xua/src/core/clocking/clockgen.xc
View File

@@ -8,8 +8,6 @@
#include "xua_commands.h" #include "xua_commands.h"
#include "xua_clocking.h" #include "xua_clocking.h"
#include <stdio.h> // TODO DEV ONLY - DELME
#ifdef __XS3A__ #ifdef __XS3A__
#define USE_SW_PLL 1 #define USE_SW_PLL 1
#else #else
@@ -306,22 +304,35 @@ void do_sw_pll_phase_frequency_detector( sw_pll_state_t sw_pll,
chanend c_sigma_delta, chanend c_sigma_delta,
int receivedSamples) int receivedSamples)
{ {
const unsigned control_loop_rate_divider = 6; /* 300Hz * 2 edges / 6 -> 100Hz loop rate */
static unsigned control_loop_counter = 0;
static unsigned total_received_samples = 0;
/* Keep a store of the last mclk time stamp so we can work out the increment */ /* Keep a store of the last mclk time stamp so we can work out the increment */
static unsigned short last_mclk_time_stamp = 0; static unsigned short last_mclk_time_stamp = 0;
/* Calculate what the zero-error mclk count increment should be for this many samples */ control_loop_counter++;
const unsigned expected_mclk_inc = mclks_per_sample * receivedSamples / 2; /* divide by 2 because this fn is called per edge */
/* Calculate actualy time-stamped mclk count increment is */ total_received_samples += receivedSamples;
const unsigned short actual_mclk_inc = mclk_time_stamp - last_mclk_time_stamp;
/* The difference is the raw error in terms of mclk counts */ if(control_loop_counter == control_loop_rate_divider)
short f_error = (int)actual_mclk_inc - (int)expected_mclk_inc; {
/* Calculate what the zero-error mclk count increment should be for this many samples */
const unsigned expected_mclk_inc = mclks_per_sample * total_received_samples / 2; /* divide by 2 because this fn is called per edge */
/* send PFD output to the sigma delta thread */ /* Calculate actualy time-stamped mclk count increment is */
outuint(c_sigma_delta, (unsigned) (1000000 + f_error)); const unsigned short actual_mclk_inc = mclk_time_stamp - last_mclk_time_stamp;
last_mclk_time_stamp = mclk_time_stamp; /* The difference is the raw error in terms of mclk counts */
short f_error = (int)actual_mclk_inc - (int)expected_mclk_inc;
/* send PFD output to the sigma delta thread */
outuint(c_sigma_delta, (unsigned) (1000000 + f_error));
last_mclk_time_stamp = mclk_time_stamp;
control_loop_counter = 0;
total_received_samples = 0;
}
} }
void SigmaDeltaTask(chanend c_sigma_delta, unsigned sdm_interval){ void SigmaDeltaTask(chanend c_sigma_delta, unsigned sdm_interval){
@@ -354,7 +365,6 @@ void SigmaDeltaTask(chanend c_sigma_delta, unsigned sdm_interval){
{ {
case inuint_byref(c_sigma_delta, tmp): case inuint_byref(c_sigma_delta, tmp):
f_error = (int32_t)tmp; f_error = (int32_t)tmp;
printstr("sigma-delta got: "); printintln(f_error);
unsafe unsafe
{ {
sw_pll_sdm_do_control_from_error(sw_pll_ptr, -f_error + 1000000); sw_pll_sdm_do_control_from_error(sw_pll_ptr, -f_error + 1000000);
@@ -539,7 +549,9 @@ void clockGen ( streaming chanend ?c_spdif_rx,
chan c_sigma_delta; chan c_sigma_delta;
sw_pll_state_t sw_pll; sw_pll_state_t sw_pll;
/* Initialise before we par off the SDM task */ /* Initialise before we par off the SDM thread/
We share the sw_pll struct across threads and this
us safe because the threads access different memebers */
unsafe unsafe
{ {
sw_pll_ptr = &sw_pll; sw_pll_ptr = &sw_pll;