/*.......1.........2.........3.........4.........5.........6.........7.........8 ================================================================================ FILE climit/cfunc.mod Copyright 1991 Georgia Tech Research Corporation, Atlanta, Ga. 30332 All Rights Reserved PROJECT A-8503-405 AUTHORS 6 June 1991 Jeffrey P. Murray MODIFICATIONS 26 Sept 1991 Jeffrey P. Murray SUMMARY This file contains the functional description of the adc_bridge code model. INTERFACES FILE ROUTINE CALLED CMutil.c void cm_smooth_corner(); void cm_smooth_discontinuity(); CMmacros.h cm_message_send(); REFERENCED FILES Inputs from and outputs to ARGS structure. NON-STANDARD FEATURES NONE ===============================================================================*/ /*=== INCLUDE FILES ====================*/ /*=== CONSTANTS ========================*/ /*=== MACROS ===========================*/ /*=== LOCAL VARIABLES & TYPEDEFS =======*/ /*=== FUNCTION PROTOTYPE DEFINITIONS ===*/ /*============================================================================== FUNCTION cm_climit() AUTHORS 6 June 1991 Jeffrey P. Murray MODIFICATIONS 26 Sept 1991 Jeffrey P. Murray SUMMARY This function implements the climit code model. INTERFACES FILE ROUTINE CALLED CMutil.c void cm_smooth_corner(); void cm_smooth_discontinuity(); CMmacros.h cm_message_send(); RETURNED VALUE Returns inputs and outputs via ARGS structure. GLOBAL VARIABLES NONE NON-STANDARD FEATURES NONE ==============================================================================*/ /*=== CM_CLIMIT ROUTINE ===*/ void cm_climit(ARGS) /* structure holding parms, inputs, outputs, etc. */ { /* Define error message string constants */ char *climit_range_error = "\n**** ERROR ****\n* CLIMIT function linear range less than zero. *\n"; double lower_delta, /* lower delta value parameter */ upper_delta, /* upper delta value parameter */ limit_range, /* range of output below (out_upper_limit - upper_delta) or above (out_lower_limit + lower_delta) within which smoothing will be applied */ gain, /* gain parameter */ threshold_upper, /* = out_upper_limit - upper_delta */ threshold_lower, /* = out_lower_limit + lower_delta */ linear_range, /* = threshold_upper - threshold_lower */ out_lower_limit, /* output lower limit parameter */ out_upper_limit, /* output upper limit parameter */ out, /* originally-calculated output value */ limited_out, /* output value after limiting */ pout_pin, /* partial derivative of output w.r.t.input */ pout_pcntl_upper, /* partial derivative of output w.r.t. cntl_upper input */ pout_pcntl_lower, /* partial derivative of output w.r.t. cntl_lower input */ junk; /* dummy variable */ Mif_Complex_t ac_gain; /* AC gain */ /* Retrieve frequently used parameters... */ lower_delta = PARAM(lower_delta); upper_delta = PARAM(upper_delta); limit_range = PARAM(limit_range); gain = PARAM(gain); /* Find Upper & Lower Limits */ out_lower_limit = INPUT(cntl_lower) + lower_delta; out_upper_limit = INPUT(cntl_upper) - upper_delta; if (PARAM(fraction) == MIF_TRUE) /* Set range to absolute value */ limit_range = limit_range * (out_upper_limit - out_lower_limit); threshold_upper = out_upper_limit - /* Set Upper Threshold */ limit_range; threshold_lower = out_lower_limit + /* Set Lower Threshold */ limit_range; linear_range = threshold_upper - threshold_lower; /* Test the linear region & make sure there IS one... */ if (linear_range < 0.0) { /* This INIT test keeps the models from outputting an error message the first time through when all the inputs are initialized to zero */ if( (INIT != 1) && (0.0 != TIME) ){ cm_message_send(climit_range_error); } limited_out = 0.0; pout_pin = 0.0; pout_pcntl_lower = 0.0; pout_pcntl_upper = 0.0; return; } /* Compute Un-Limited Output */ out = gain * (PARAM(in_offset) + INPUT(in)); if (out < threshold_lower) { /* Limit Out @ Lower Bound */ pout_pcntl_upper= 0.0; if (out > (out_lower_limit - limit_range)) { /* Parabolic */ cm_smooth_corner(out,out_lower_limit,out_lower_limit, limit_range,0.0,1.0,&limited_out, &pout_pin); pout_pin = gain * pout_pin; cm_smooth_discontinuity(out,out_lower_limit,1.0,threshold_lower, 0.0,&pout_pcntl_lower,&junk); } else { /* Hard-Limited Region */ limited_out = out_lower_limit; pout_pin = 0.0; pout_pcntl_lower = 1.0; } } else { if (out > threshold_upper) { /* Limit Out @ Upper Bound */ pout_pcntl_lower= 0.0; if (out < (out_upper_limit+limit_range)) { /* Parabolic */ cm_smooth_corner(out,out_upper_limit,out_upper_limit, limit_range,1.0,0.0,&limited_out, &pout_pin); pout_pin = gain * pout_pin; cm_smooth_discontinuity(out,threshold_upper,0.0,out_upper_limit, 1.0,&pout_pcntl_upper,&junk); } else { /* Hard-Limited Region */ limited_out = out_upper_limit; pout_pin = 0.0; pout_pcntl_upper = 1.0; } } else { /* No Limiting Needed */ limited_out = out; pout_pin = gain; pout_pcntl_lower = 0.0; pout_pcntl_upper = 0.0; } } if (ANALYSIS != MIF_AC) { /* DC & Transient Analyses */ OUTPUT(out) = limited_out; PARTIAL(out,in) = pout_pin; PARTIAL(out,cntl_lower) = pout_pcntl_lower; PARTIAL(out,cntl_upper) = pout_pcntl_upper; } else { /* AC Analysis */ ac_gain.real = pout_pin; ac_gain.imag= 0.0; AC_GAIN(out,in) = ac_gain; ac_gain.real = pout_pcntl_lower; ac_gain.imag= 0.0; AC_GAIN(out,cntl_lower) = ac_gain; ac_gain.real = pout_pcntl_upper; ac_gain.imag= 0.0; AC_GAIN(out,cntl_upper) = ac_gain; } }