probe.c

00001 /*
00002   probe.c - code pertaining to probing methods
00003   Part of Grbl
00004 
00005   Copyright (c) 2014-2016 Sungeun K. Jeon for Gnea Research LLC
00006 
00007   Grbl is free software: you can redistribute it and/or modify
00008   it under the terms of the GNU General Public License as published by
00009   the Free Software Foundation, either version 3 of the License, or
00010   (at your option) any later version.
00011 
00012   Grbl is distributed in the hope that it will be useful,
00013   but WITHOUT ANY WARRANTY; without even the implied warranty of
00014   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00015   GNU General Public License for more details.
00016 
00017   You should have received a copy of the GNU General Public License
00018   along with Grbl.  If not, see <http://www.gnu.org/licenses/>.
00019 */
00020 
00021 #include "grbl.h"
00022 
00023 
00024 // Inverts the probe pin state depending on user settings and probing cycle mode.
00025 uint8_t probe_invert_mask;
00026 
00027 
00028 // Probe pin initialization routine.
00029 void probe_init()
00030 {
00031 #ifdef AVRTARGET
00032   PROBE_DDR &= ~(PROBE_MASK); // Configure as input pins
00033   #ifdef DISABLE_PROBE_PIN_PULL_UP
00034     PROBE_PORT &= ~(PROBE_MASK); // Normal low operation. Requires external pull-down.
00035   #else
00036     PROBE_PORT |= PROBE_MASK;    // Enable internal pull-up resistors. Normal high operation.
00037   #endif
00038 #endif
00039 #ifdef STM32F103C8
00040     GPIO_InitTypeDef GPIO_InitStructure;
00041     RCC_APB2PeriphClockCmd(RCC_PROBE_PORT, ENABLE);
00042     GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
00043 #ifdef DISABLE_PROBE_PIN_PULL_UP
00044     GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
00045 #else
00046     GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
00047 #endif
00048     GPIO_InitStructure.GPIO_Pin = PROBE_MASK;
00049     GPIO_Init(PROBE_PORT, &GPIO_InitStructure);
00050 #endif
00051   probe_configure_invert_mask(false); // Initialize invert mask.
00052 }
00053 
00054 
00055 // Called by probe_init() and the mc_probe() routines. Sets up the probe pin invert mask to
00056 // appropriately set the pin logic according to setting for normal-high/normal-low operation
00057 // and the probing cycle modes for toward-workpiece/away-from-workpiece.
00058 void probe_configure_invert_mask(uint8_t is_probe_away)
00059 {
00060   probe_invert_mask = 0; // Initialize as zero.
00061   if (bit_isfalse(settings.flags,BITFLAG_INVERT_PROBE_PIN)) { probe_invert_mask ^= PROBE_MASK; }
00062   if (is_probe_away) { probe_invert_mask ^= PROBE_MASK; }
00063 }
00064 
00065 
00066 // Returns the probe pin state. Triggered = true. Called by gcode parser and probe state monitor.
00067 uint8_t probe_get_state() 
00068 { 
00069 #ifdef AVRTARGET
00070     return((PROBE_PIN & PROBE_MASK) ^ probe_invert_mask); 
00071 #endif
00072 #ifdef WIN32
00073     return 0;
00074 #endif
00075 #ifdef STM32F103C8
00076     return ((GPIO_ReadInputData(PROBE_PORT) & PROBE_MASK) ^ probe_invert_mask) != 0;
00077 #endif
00078 }
00079 
00080 
00081 // Monitors probe pin state and records the system position when detected. Called by the
00082 // stepper ISR per ISR tick.
00083 // NOTE: This function must be extremely efficient as to not bog down the stepper ISR.
00084 void probe_state_monitor()
00085 {
00086   if (probe_get_state()) {
00087     sys_probe_state = PROBE_OFF;
00088     memcpy(sys_probe_position, sys_position, sizeof(sys_position));
00089     bit_true(sys_rt_exec_state, EXEC_MOTION_CANCEL);
00090   }
00091 }