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authorJosh Blum <josh@joshknows.com>2011-01-29 21:03:29 +0000
committerJosh Blum <josh@joshknows.com>2011-01-29 21:03:29 +0000
commit572a64f0acb459583abfccbc8288158822fa2f77 (patch)
tree4f75150a25958a646514b4a6e60ec7f57dd174bd /host/lib/usrp
parentef6331f622aacadf233369637e08bfb7f2e6995a (diff)
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usrp-e100: clock control use boost math gcd for divider calculation
Diffstat (limited to 'host/lib/usrp')
-rw-r--r--host/lib/usrp/usrp_e100/clock_ctrl.cpp11
1 files changed, 7 insertions, 4 deletions
diff --git a/host/lib/usrp/usrp_e100/clock_ctrl.cpp b/host/lib/usrp/usrp_e100/clock_ctrl.cpp
index e2c4889bc..dd7f8507b 100644
--- a/host/lib/usrp/usrp_e100/clock_ctrl.cpp
+++ b/host/lib/usrp/usrp_e100/clock_ctrl.cpp
@@ -24,6 +24,7 @@
#include <boost/foreach.hpp>
#include <boost/format.hpp>
#include <boost/operators.hpp>
+#include <boost/math/common_factor_rt.hpp> //gcd
#include <algorithm>
#include <utility>
#include <iostream>
@@ -216,12 +217,14 @@ public:
_chan_rate = rate;
_out_rate = rate;
- _ad9522_regs.enable_clock_doubler = 1;
+ _ad9522_regs.enable_clock_doubler = 1; //doubler always on
+ const double ref_rate = REFERENCE_INPUT_RATE*2;
- //bypass prescalers and counters == 1
- _ad9522_regs.set_r_counter(125);
+ //bypass prescaler such that N = B
+ long gcd = boost::math::gcd(long(ref_rate), long(rate));
+ _ad9522_regs.set_r_counter(int(ref_rate/gcd));
_ad9522_regs.a_counter = 0;
- _ad9522_regs.set_b_counter(384);
+ _ad9522_regs.set_b_counter(int(rate/gcd));
_ad9522_regs.prescaler_p = ad9522_regs_t::PRESCALER_P_DIV1;
//setup external vcxo