CommandStation-EX/FSH.h

94 lines
3.2 KiB
C

/*
* © 2022 Paul M. Antoine
* © 2021 Neil McKechnie
* © 2021 Harald Barth
* © 2021 Fred Decker
* All rights reserved.
*
* This file is part of CommandStation-EX
*
* This is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* It is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with CommandStation. If not, see <https://www.gnu.org/licenses/>.
*/
#ifndef FSH_h
#define FSH_h
/* This is an architecture support file to manage the differences
* between the nano/uno.mega and the later nanoEvery, unoWifiRev2 etc
*
* IMPORTANT:
* To maintain portability the main code should NOT contain ANY references
* to the following:
*
* __FlashStringHelper Use FSH instead.
* PROGMEM use FLASH instead
* pgm_read_byte_near use GETFLASH instead.
* pgm_read_word_near use GETFLASHW instead.
*
* Also:
* HIGHFLASH - PROGMEM forced to end of link so needs far pointers.
* GETHIGHFLASH,GETHIGHFLASHW to access them
*
*/
#include <Arduino.h>
#ifdef ARDUINO_ARCH_AVR
// AVR devices have flash memory mapped differently
// progmem can be accessed by _near functions or _far
typedef __FlashStringHelper FSH;
#define FLASH PROGMEM
#define GETFLASH(addr) pgm_read_byte_near(addr)
#define STRCPY_P strcpy_P
#define STRCMP_P strcmp_P
#define STRNCPY_P strncpy_P
#define STRNCMP_P strncmp_P
#define STRLEN_P strlen_P
#if defined(ARDUINO_AVR_MEGA) || defined(ARDUINO_AVR_MEGA2560)
// AVR_MEGA memory deliberately placed at end of link may need _far functions
#define HIGHFLASH __attribute__((section(".fini2")))
#define GETFARPTR(data) pgm_get_far_address(data)
#define GETHIGHFLASH(data,offset) pgm_read_byte_far(GETFARPTR(data)+offset)
#define GETHIGHFLASHW(data,offset) pgm_read_word_far(GETFARPTR(data)+offset)
#else
// AVR_UNO/NANO runtime does not support _far functions so just use _near equivalent
// as there is no progmem above 32kb anyway.
#define HIGHFLASH PROGMEM
#define GETFARPTR(data) ((uint32_t)(data))
#define GETHIGHFLASH(data,offset) pgm_read_byte_near(GETFARPTR(data)+(offset))
#define GETHIGHFLASHW(data,offset) pgm_read_word_near(GETFARPTR(data)+(offset))
#endif
#else
// Non-AVR Flat-memory devices have no need of this support so can be remapped to normal memory access
#ifdef F
#undef F
#endif
#ifdef FLASH
#undef FLASH
#endif
#define F(str) (str)
typedef char FSH;
#define FLASH
#define HIGHFLASH
#define GETFARPTR(data) ((uint32_t)(data))
#define GETFLASH(addr) (*(const byte *)(addr))
#define GETHIGHFLASH(data,offset) (*(const byte *)(GETFARPTR(data)+offset))
#define GETHIGHFLASHW(data,offset) (*(const uint16_t *)(GETFARPTR(data)+offset))
#define STRCPY_P strcpy
#define STRCMP_P strcmp
#define STRNCPY_P strncpy
#define STRNCMP_P strncmp
#define STRLEN_P strlen
#endif
#endif