Protocol: AhYX  Sequence: ahYX.c  Apptype: solidseq1d

Description: 

A 2D sequence to provide YX correlation with HYX double cross 
polarization. The F1 period follows HY CP,and F2 acquisition
follows YX CP after a Z-filter period, tZF. 
 
Decoupling during F1 and F2 uses either SPINAL or TPPM
and a rotor-synchronized constant-time option, t2max, is 
provided for F1 acquisition with a simpulse. For standard 
acquisition d2, X refocusing during F1 is provided by a 
composite pulse. A constant-time decoupling period, tRF,
follows acquisition to compensate d2 or t2max. 

The sequence forces rotor synchronization of the constant-
time F1 based on srate and forces tRF to be at least d2 
or t2max.

Acknowledgement:

Sequence provided by Chad Reinstra UIUC as hYXX.c. 

Setup:

Load an exisiting dataset or type Settancpx. Type AhYX, select 
the desired options and determine calibrations for the desired
experiment. 

Special Parameters: 

DecouplingH: Hseq='tppm' or 'spinal'.
Standard F1 (ctN='n'): d2 and composite-X refocussing, 4*pwX90. 
Constant Time F1 (ctN ='y'): d2, t2max, simpulse, 2*pwX90 and 2.0*pwY90
Constant Time Decoupling: tRF - (d2 (std) or t2max 
   (constant-time decoupling))
Z-filter: 2(ea) pwX90, tZH and aZF 

Parameter Groups: 

cpHY:  Module:  yes
Sequence:  dcptan.c
Description:  Implements constant, linear or tangent-ramped cross
              polarization from dec to dec2.
Parameters:  Sequence Page
       shHY - 'c', constant, 'l', linear and 't', tangent shape on the
              channel designated with
                      chHY.
       chHY - the variable-amplitude channel, 'fr' from or 'to', to.
       aHhy - median amplitude of the dec channel.
       aXhy - median amplitude of the dec2 channel.
       bHY - tangent curvature (>0 to 1.0e5).
       dHY - +/- amplitude width of the ramp. A negative width sets a
              ramp that starts high and decreases in amplitude.
       tHY - contact time.
       ofHY - overall offset on the variable channel.
       frHY = 'dec' - channel with the initial polarization (must be
              set - not shown).   
       toHY = 'dec2' - channel with the final polarization (must be set
              - not shown).
Implementation: CP hy = getcp("HY",0.0,0.0,0,1);
Underscore function: _cp_(hy,phHhx,phYhy); phHhx is the overall phase
              table for the H channel and phYhy is that for the Y channel.

cpYX:  Module:  yes
Sequence: dcptan.c
Description:  Implements constant, linear or tangent-ramped cross
              polarization from dec2 to obs.
Parameters:  Sequence Page
       shYX - 'c', constant, 'l', linear and 't', tangent shape on the
              channel designated with chYX.
       chYX - the variable-amplitude channel, 'fr' from or 'to', to.
       aYyx - median amplitude of the dec2 channel.
       aXyx - median amplitude of the obs channel.
       bYX - tangent curvature (>0 to 1.0e5).
       dYX - +/- amplitude width of the ramp. A negative width sets a
              ramp that starts high and decreases in amplitude.
       tYX - contact time.
       ofYX - overall offset on the variable channel.
       frYX = 'dec2' - channel with the initial polarization (must be
              set - not shown).
       toYX = 'obs' - channel with the final polarization (must be set
              - not shown).
Implementation: CP yx = getcp("YX",0.0,0.0,0,1);
Underscore function: _cp_(yx,phYyx,phXhx); phYyx is the overall phase
              table for the Y channel and phXhx is that for the X channel.

90X:  Module:  no
Sequence:  onepul.c
Description:  Provides a 90-degree pulse on obs that is used in a composite 
              refocusing pulse during F1.  
Parameters:  Channels Page
      aX90  - the amplitude of the pulse.
      pwX90 - the pulse length.

Hseq:  Module: yes (implementation 2 for SPINAL (2-angle) and TPPM)
Sequence:  tancpx.c and ahX.c
Description:  Chooses SPINAL, SPINAL2, TPPM or WALTZ decoupling on 
              the dec channel during acquisition.
Parameters:   Sequence Page - The Hspinal, Htppm and other groups
              overlap.  Hseq chooses the decoupling sequences TPPM
              SPINAL, SPINAL2 or WALTZ. 
Implementation:  DSEQ dec = getdseq("H"); The router implements
              getspinal(), getspinal2(), gettppm() or getwaltz(), as
              selected.
Implementation2: DSEQ dec = getdseq2("H"); The router implements
              getspinal2s(), gettppm() or getwaltz(), as selected.
Underscore functions:  _dseqon(dec); runs _tppm(); _spinal(); _spinal2 
              or _waltz, as selected. dseqoff(dec); runs decprgoff(dec);
Underscore functions2:  _dseqon2(dec); runs _tppm(); _spinal2() or _waltz();
             _dseqoff2(dec); runs decprgoff();

Hspinal:  Module: yes
Sequence:  tancpx.c and ahX.c
Description:  Implements (2-angle) SPINAL2 decoupling on the dec channel 
              with the dseq2 module.
Parameters:  Sequence Page
       aHspinal - amplitude of the dec channel.
       pwHspinal - approximate 180-degree flip.
       phHspinal - +/- small angle phase. SPINAL64 (1) is implemented
              with phases = +/- 1.0, +/- 1.5 and +/-2.0 times
              phHspinal or (2) is implemented with phases = +/- phHspinal, 
              +/- (phHspinal + alpHspinal) and +/- (phHspinal + 2.0*alpHspinal).
       alpHspinal - second angle - set 0.0 for TPPM and phHspinal/2.0
                     for standard SPINAL64.             
       chHspinal = 'dec' must be set (not shown).
Implementation: SPINAL dec = getspinal("H"); or DSEQ dec = getdseq("H");
Implementation2: SPINAL2 dec = getspinal2s("H"); or DSEQ dec = getdseq2("H");
Underscore functions: _spinal(dec); and decprgoff(); or _dseqon(dec);
             and _dseqoff(dec);
Underscore functions2: _spinal2(dec); and decprgoff(); or _dseqon2(dec);
             and _dseqoff2(dec);
        
Htppm:  Module: yes
Sequence:  tancpx.c and ahX.c
Description:  Implements TPPM decoupling on the dec channel with the 
              dseq2 module.  
Parameters:  Sequence Page
       aHtppm - amplitude of the dec channel.
       pwHtppm - approximate 180-degree flip angle on resonance.
       phHtppm - +/- small angle phase. TPPM is implemented
              with phases = +/- 1.0 times phHtppm for alternating
              pulses.
       chHtppm = 'dec' must be set (not shown).
Implementation: TPPM dec = gettppm("H"); or DSEQ dec = getdseq("H");
Implementation2: DSEQ dec = getdseq2("H");
Underscore functions: _tppm(dec); and decprgoff(); or _dseqon(dec); and
              _dseqoff(dec);
Underscore functions2: _dseqon2(dec); and _dseqoff2(dec);
