78 lines
2.2 KiB
C
78 lines
2.2 KiB
C
/**
|
|
* Marlin 3D Printer Firmware
|
|
* Copyright (C) 2016 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
|
|
*
|
|
* Based on Sprinter and grbl.
|
|
* Copyright (C) 2011 Camiel Gubbels / Erik van der Zalm
|
|
*
|
|
* This program 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.
|
|
*
|
|
* This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*
|
|
*/
|
|
|
|
/**
|
|
* AVR busy wait delay Cycles routines:
|
|
*
|
|
* DELAY_CYCLES(count): Delay execution in cycles
|
|
* DELAY_NS(count): Delay execution in nanoseconds
|
|
* DELAY_US(count): Delay execution in microseconds
|
|
*/
|
|
|
|
#ifndef MARLIN_DELAY_H
|
|
#define MARLIN_DELAY_H
|
|
|
|
#define nop() __asm__ __volatile__("nop;\n\t":::)
|
|
|
|
FORCE_INLINE static void __delay_4cycles(uint8_t cy) {
|
|
__asm__ __volatile__(
|
|
L("1")
|
|
A("dec %[cnt]")
|
|
A("nop")
|
|
A("brne 1b")
|
|
: [cnt] "+r"(cy) // output: +r means input+output
|
|
: // input:
|
|
: "cc" // clobbers:
|
|
);
|
|
}
|
|
|
|
/* ---------------- Delay in cycles */
|
|
FORCE_INLINE static void DELAY_CYCLES(uint16_t x) {
|
|
|
|
if (__builtin_constant_p(x)) {
|
|
#define MAXNOPS 4
|
|
|
|
if (x <= (MAXNOPS)) {
|
|
switch (x) { case 4: nop(); case 3: nop(); case 2: nop(); case 1: nop(); }
|
|
}
|
|
else {
|
|
const uint32_t rem = (x) % (MAXNOPS);
|
|
switch (rem) { case 3: nop(); case 2: nop(); case 1: nop(); }
|
|
if ((x = (x) / (MAXNOPS)))
|
|
__delay_4cycles(x); // if need more then 4 nop loop is more optimal
|
|
}
|
|
|
|
#undef MAXNOPS
|
|
}
|
|
else
|
|
__delay_4cycles(x / 4);
|
|
}
|
|
#undef nop
|
|
|
|
/* ---------------- Delay in nanoseconds */
|
|
#define DELAY_NS(x) DELAY_CYCLES( (x) * (F_CPU/1000000L) / 1000L )
|
|
|
|
/* ---------------- Delay in microseconds */
|
|
#define DELAY_US(x) DELAY_CYCLES( (x) * (F_CPU/1000000L) )
|
|
|
|
#endif // MARLIN_DELAY_H
|