view src/cs/layer1/gtt_include/ctm/m_sequence.h @ 629:3231dd9b38c1

armio.c: make GPIOs 8 & 13 outputs driving 1 on all "classic" targets Calypso GPIOs 8 & 13 are pinmuxed with MCUEN1 & MCUEN2, respectively, and on powerup these pins are MCUEN, i.e., outputs driving 1. TI's code for C-Sample and earlier turns them into GPIOs configured as outputs also driving 1 - so far, so good - but TI's code for BOARD 41 (which covers D-Sample, Leonardo and all real world Calypso devices derived from the latter) switches them from MCUEN to GPIOs, but then leaves them as inputs. Given that the hardware powerup state of these two pins is outputs driving 1, every Calypso board design MUST be compatible with such driving; typically these GPIO signals will be either unused and unconnected or connected as outputs driving some peripheral. Turning these pins into GPIO inputs will result in floating inputs on every reasonably-wired board, thus I am convinced that this configuration is nothing but a bug on the part of whoever wrote this code at TI. This floating input bug had already been fixed earlier for GTA modem and FCDEV3B targets; the present change makes the fix unconditional for all "classic" targets. The newly affected targets are D-Sample, Leonardo, Tango and GTM900.
author Mychaela Falconia <falcon@freecalypso.org>
date Thu, 02 Jan 2020 05:38:26 +0000
parents 945cf7f506b2
children
line wrap: on
line source

/*
*******************************************************************************
*
*      COPYRIGHT (C) 2000 BY ERICSSON EUROLAB DEUTSCHLAND GmbH
*      90411 NUERNBERG, GERMANY, Tel Int + 49 911 5217 100
*
*      The program(s) may be used and/or copied only with the
*      written permission from Ericsson or in accordance
*      with the terms and conditions stipulated in the agreement or
*      contract under which the program(s) have been supplied.
*
*******************************************************************************
*
*      File             : m_sequence.h
*      Purpose          : Calculation of m-sequences 
*                         (maximum-length sequecnes or pseudo noise)
*
*******************************************************************************
*/

#ifndef m_sequence_h
#define m_sequence_h "$Id: $"

/*
*******************************************************************************
*                         INCLUDE FILES
*******************************************************************************
*/


/*
*******************************************************************************
*                         DECLARATION OF PROTOTYPES
*******************************************************************************
*/

/* -------------------------------------------------------------------- */
/* function m_sequence()                                                */
/* *********************                                                */
/* Calculates one period of an m-sequence (binary pseudo noise).        */
/* The sequence is stored in the vector sequence, which must have a     */
/* of (2^r)-1, where r is an integer number between 2 and 10.           */
/* Therefore, with this release of m_sequence, sequences of length      */
/* 3, 7, 15, 31, 63, 127, 255, 511, or 1023 can be generated.           */
/* The resulting sequence is bipolar, i.e. it has values -1 and +1.     */
/* -------------------------------------------------------------------- */

void m_sequence(WORD16 *sequence, WORD16 length);


#endif