Simplified use of the AD9910 RAM feature (#1584)

* coredevice: Change Urukul default single-tone profile to 7

This allows using the internal profile control in RAM modulation mode (which always starts to play back at profile 0) without competing for the content of the profile 0 register used in single tone mode.

Signed-off-by: Peter Drmota <peter.drmota@physics.ox.ac.uk>

* ad9910/set_mu: comment on caveats when setting register

* ad9910: avoid unnecessary write/param

Credit: Solution proposed by @pmldrmota in https://github.com/m-labs/artiq/pull/1584#issuecomment-987774353

* revert 1064fdff (`set_mu()` comments)

158a7be7 had addressed this issue.

Co-authored-by: occheung <dc@m-labs.hk>

RELEASE_NOTES.rst

@@ -84,8 +84,11 @@ Highlights:
    - Improved performance for kernel RPC involving list and array.
 * Coredevice SI to mu conversions now always return valid codes, or raise a ``ValueError``.
 * Zotino now exposes  ``voltage_to_mu()``
-* ``ad9910``: The maximum amplitude scale factor is now ``0x3fff`` (was ``0x3ffe``
-  before).
+* ``ad9910``: 
+   - The maximum amplitude scale factor is now ``0x3fff`` (was ``0x3ffe`` before).
+   - The default single-tone profile is now 7 (was 0).
+   - Added option to ``set_mu()`` that affects the ASF, FTW and POW registers
+     instead of the single-tone profile register.
 * Mirny now supports HW revision independent, human readable ``clk_sel`` parameters:
   "XO", "SMA", and "MMCX". Passing an integer is backwards compatible.
 * Dashboard:

artiq/coredevice/ad9910.py

@@ -236,7 +236,7 @@ class AD9910:
         """
         self.bus.set_config_mu(urukul.SPI_CONFIG | spi.SPI_END, 24,
                                urukul.SPIT_DDS_WR, self.chip_select)
-        self.bus.write((addr << 24) | (data << 8))
+        self.bus.write((addr << 24) | ((data & 0xffff) << 8))
 
     @kernel
     def write32(self, addr: TInt32, data: TInt32):
@@ -516,10 +516,11 @@ class AD9910:
         self.cpld.io_update.pulse(1 * us)
 
     @kernel
-    def set_mu(self, ftw: TInt32, pow_: TInt32 = 0, asf: TInt32 = 0x3fff,
+    def set_mu(self, ftw: TInt32 = 0, pow_: TInt32 = 0, asf: TInt32 = 0x3fff,
                phase_mode: TInt32 = _PHASE_MODE_DEFAULT,
-               ref_time_mu: TInt64 = int64(-1), profile: TInt32 = 0) -> TInt32:
-        """Set profile 0 data in machine units.
+               ref_time_mu: TInt64 = int64(-1), profile: TInt32 = 7,
+               ram_destination: TInt32 = -1) -> TInt32:
+        """Set DDS data in machine units.
 
         This uses machine units (FTW, POW, ASF). The frequency tuning word
         width is 32, the phase offset word width is 16, and the amplitude
@@ -538,7 +539,13 @@ class AD9910:
             by :meth:`set_phase_mode` for this call.
         :param ref_time_mu: Fiducial time used to compute absolute or tracking
             phase updates. In machine units as obtained by `now_mu()`.
-        :param profile: Profile number to set (0-7, default: 0).
+        :param profile: Single tone profile number to set (0-7, default: 7).
+            Ineffective if `ram_destination` is specified.
+        :param ram_destination: RAM destination (:const:`RAM_DEST_FTW`,
+            :const:`RAM_DEST_POW`, :const:`RAM_DEST_ASF`,
+            :const:`RAM_DEST_POWASF`). If specified, write free DDS parameters
+            to the ASF/FTW/POW registers instead of to the single tone profile
+            register (default behaviour, see `profile`).
         :return: Resulting phase offset word after application of phase
             tracking offset. When using :const:`PHASE_MODE_CONTINUOUS` in
             subsequent calls, use this value as the "current" phase.
@@ -561,8 +568,17 @@ class AD9910:
                 # is equivalent to an output pipeline latency.
                 dt = int32(now_mu()) - int32(ref_time_mu)
                 pow_ += dt * ftw * self.sysclk_per_mu >> 16
+        if ram_destination == -1:
             self.write64(_AD9910_REG_PROFILE0 + profile,
                          (asf << 16) | (pow_ & 0xffff), ftw)
+        else:
+            if not ram_destination == RAM_DEST_FTW:
+                self.set_ftw(ftw)
+            if not ram_destination == RAM_DEST_POWASF:
+                if not ram_destination == RAM_DEST_ASF:
+                    self.set_asf(asf)
+                if not ram_destination == RAM_DEST_POW:
+                    self.set_pow(pow_)
         delay_mu(int64(self.sync_data.io_update_delay))
         self.cpld.io_update.pulse_mu(8)  # assumes 8 mu > t_SYN_CCLK
         at_mu(now_mu() & ~7)  # clear fine TSC again
@@ -821,10 +837,11 @@ class AD9910:
         return self.pow_to_turns(self.get_pow())
 
     @kernel
-    def set(self, frequency: TFloat, phase: TFloat = 0.0,
+    def set(self, frequency: TFloat = 0.0, phase: TFloat = 0.0,
             amplitude: TFloat = 1.0, phase_mode: TInt32 = _PHASE_MODE_DEFAULT,
-            ref_time_mu: TInt64 = int64(-1), profile: TInt32 = 0) -> TFloat:
-        """Set profile 0 data in SI units.
+            ref_time_mu: TInt64 = int64(-1), profile: TInt32 = 7,
+            ram_destination: TInt32 = -1) -> TFloat:
+        """Set DDS data in SI units.
 
         .. seealso:: :meth:`set_mu`
 
@@ -833,13 +850,14 @@ class AD9910:
         :param amplitude: Amplitude in units of full scale
         :param phase_mode: Phase mode constant
         :param ref_time_mu: Fiducial time stamp in machine units
-        :param profile: Profile to affect
+        :param profile: Single tone profile to affect.
+        :param ram_destination: RAM destination.
         :return: Resulting phase offset in turns
         """
         return self.pow_to_turns(self.set_mu(
             self.frequency_to_ftw(frequency), self.turns_to_pow(phase),
             self.amplitude_to_asf(amplitude), phase_mode, ref_time_mu,
-            profile))
+            profile, ram_destination))
 
     @kernel
     def get(self, profile: TInt32 = 0) -> TTuple([TFloat, TFloat, TFloat]):

artiq/coredevice/urukul.py

@@ -188,7 +188,7 @@ class CPLD:
             assert sync_div is None
             sync_div = 0
 
-        self.cfg_reg = urukul_cfg(rf_sw=rf_sw, led=0, profile=0,
+        self.cfg_reg = urukul_cfg(rf_sw=rf_sw, led=0, profile=7,
                                   io_update=0, mask_nu=0, clk_sel=clk_sel,
                                   sync_sel=sync_sel,
                                   rst=0, io_rst=0, clk_div=clk_div)