[
  {
    "path": ".gitignore",
    "content": "# Object files\n*.o\n*.ko\n*.obj\n*.elf\n\n# Precompiled Headers\n*.gch\n*.pch\n\n# Libraries\n*.lib\n*.a\n*.la\n*.lo\n\n# Shared objects (inc. Windows DLLs)\n*.dll\n*.so\n*.so.*\n*.dylib\n\n# Executables\n*.exe\n*.out\n*.app\n*.i*86\n*.x86_64\n*.hex\n\n# Debug files\n*.dSYM/\n*.su\n"
  },
  {
    "path": "LICENSE",
    "content": "                    GNU GENERAL PUBLIC LICENSE\n                       Version 2, June 1991\n\n Copyright (C) 1989, 1991 Free Software Foundation, Inc., <http://fsf.org/>\n 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA\n Everyone is permitted to copy and distribute verbatim copies\n of this license document, but changing it is not allowed.\n\n                            Preamble\n\n  The licenses for most software are designed to take away your\nfreedom to share and change it.  By contrast, the GNU General Public\nLicense is intended to guarantee your freedom to share and change free\nsoftware--to make sure the software is free for all its users.  This\nGeneral Public License applies to most of the Free Software\nFoundation's software and to any other program whose authors commit to\nusing it.  (Some other Free Software Foundation software is covered by\nthe GNU Lesser General Public License instead.)  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You may copy and distribute verbatim copies of the Program's\nsource code as you receive it, in any medium, provided that you\nconspicuously and appropriately publish on each copy an appropriate\ncopyright notice and disclaimer of warranty; keep intact all the\nnotices that refer to this License and to the absence of any warranty;\nand give any other recipients of the Program a copy of this License\nalong with the Program.\n\nYou may charge a fee for the physical act of transferring a copy, and\nyou may at your option offer warranty protection in exchange for a fee.\n\n  2. 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IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING\nWILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR\nREDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,\nINCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING\nOUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED\nTO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY\nYOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER\nPROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE\nPOSSIBILITY OF SUCH DAMAGES.\n\n                     END OF TERMS AND CONDITIONS\n\n            How to Apply These Terms to Your New Programs\n\n  If you develop a new program, and you want it to be of the greatest\npossible use to the public, the best way to achieve this is to make it\nfree software which everyone can redistribute and change under these terms.\n\n  To do so, attach the following notices to the program.  It is safest\nto attach them to the start of each source file to most effectively\nconvey the exclusion of warranty; and each file should have at least\nthe \"copyright\" line and a pointer to where the full notice is found.\n\n    {description}\n    Copyright (C) {year}  {fullname}\n\n    This program is free software; you can redistribute it and/or modify\n    it under the terms of the GNU General Public License as published by\n    the Free Software Foundation; either version 2 of the License, or\n    (at your option) any later version.\n\n    This program is distributed in the hope that it will be useful,\n    but WITHOUT ANY WARRANTY; without even the implied warranty of\n    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\n    GNU General Public License for more details.\n\n    You should have received a copy of the GNU General Public License along\n    with this program; if not, write to the Free Software Foundation, Inc.,\n    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.\n\nAlso add information on how to contact you by electronic and paper mail.\n\nIf the program is interactive, make it output a short notice like this\nwhen it starts in an interactive mode:\n\n    Gnomovision version 69, Copyright (C) year name of author\n    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.\n    This is free software, and you are welcome to redistribute it\n    under certain conditions; type `show c' for details.\n\nThe hypothetical commands `show w' and `show c' should show the appropriate\nparts of the General Public License.  Of course, the commands you use may\nbe called something other than `show w' and `show c'; they could even be\nmouse-clicks or menu items--whatever suits your program.\n\nYou should also get your employer (if you work as a programmer) or your\nschool, if any, to sign a \"copyright disclaimer\" for the program, if\nnecessary.  Here is a sample; alter the names:\n\n  Yoyodyne, Inc., hereby disclaims all copyright interest in the program\n  `Gnomovision' (which makes passes at compilers) written by James Hacker.\n\n  {signature of Ty Coon}, 1 April 1989\n  Ty Coon, President of Vice\n\nThis General Public License does not permit incorporating your program into\nproprietary programs.  If your program is a subroutine library, you may\nconsider it more useful to permit linking proprietary applications with the\nlibrary.  If this is what you want to do, use the GNU Lesser General\nPublic License instead of this License.\n"
  },
  {
    "path": "README.md",
    "content": "# ESP8266_new_pwm\nThis is a drop-in replacement for the ESP8266 SDK PWM\n\nIf you like this project and want to support this and my other works, consider donating on Liberapay:\n\n<img src=\"https://img.shields.io/liberapay/patrons/StefanB.svg?logo=liberapay\"> <a href=\"https://liberapay.com/StefanB/donate\"><img alt=\"Donate using Liberapay\" src=\"https://liberapay.com/assets/widgets/donate.svg\"></a>\n\nThe software PWM provided in the ESP8266 SDK from Espressif has several drawbacks:\n\n1. Duty cycle limited to 90% (at 1kHz PWM period)\n2. usable PWM period at most ~2KHz.\n3. Incomplete documentation\n \nThis replacement allows duty cycles from 0% to 100%, with a stepsize of 200ns.\nThis is 5000 steps for a 1kHz PWM, and 256 steps (8 bit of resolution) at 19kHz.\n\nIf all channels are in steady state (either 0% of 100% in any combination),\nthe implementation goes to full idle, e.g. no interrupts.\n\nThe code is a drop-in replacement for the SDK, it provides the same functions\nas the SDK libpwm.a closed binary library. Just add pwm.c to your project.\n\nBy default there is one small difference to the SDK. The code uses a unit of\n200ns for both period and duty. E.g. for 10% duty cycle at 1kHz you need to\nspecify a period value of 5000 and a duty cycle value of 500, a duty cycle of\n5000 or above switches the channel to full on.\n\nTo have full compatibility with the SDK, you have to set the\nSDK_PWM_PERIOD_COMPAT_MODE define to 1. If set, the code will use 1us for PWM\nperiod and 40ns for the duty cycle. E.g. 10% duty cycle at 1kHz is set by a\nperiod value of 1000 and a duty cycle value of 2500, full duty at 25000 and\nabove.\n\nExample usage:\n\n\t#define PWM_CHANNELS 5\n\tconst uint32_t period = 5000; // * 200ns ^= 1 kHz\n\n\t// PWM setup\n\tuint32 io_info[PWM_CHANNELS][3] = {\n\t\t// MUX, FUNC, PIN\n\t\t{PERIPHS_IO_MUX_MTDI_U,  FUNC_GPIO12, 12},\n\t\t{PERIPHS_IO_MUX_MTDO_U,  FUNC_GPIO15, 15},\n\t\t{PERIPHS_IO_MUX_MTCK_U,  FUNC_GPIO13, 13},\n\t\t{PERIPHS_IO_MUX_MTMS_U,  FUNC_GPIO14, 14},\n\t\t{PERIPHS_IO_MUX_GPIO5_U, FUNC_GPIO5 ,  5},\n\t};\n\n\t// initial duty: all off\n\tuint32 pwm_duty_init[PWM_CHANNELS] = {0, 0, 0, 0, 0};\n\n\tpwm_init(period, pwm_duty_init, PWM_CHANNELS, io_info);\n\tpwm_start();\n\n\t// do something like this whenever you want to change duty\n\tpwm_set_duty(500, 1);  // GPIO15: 10%\n\tpwm_set_duty(5000, 1); // GPIO15: 100%\n\tpwm_start();           // commit\n\n**CAVEATS**\n\n- **To set 100% duty, the duty must be *equal* to the period**\n- **The code uses the TIMER1 interrupt. If you use e.g. the\n  softtimer, there is a conflict. You can use NM1 for the PWM\n  instead.**\n"
  },
  {
    "path": "pwm.c",
    "content": "/*\n * Copyright (C) 2016 Stefan Brüns <stefan.bruens@rwth-aachen.de>\n *\n * This program is free software; you can redistribute it and/or modify\n * it under the terms of the GNU General Public License as published by\n * the Free Software Foundation; either version 2 of the License, or\n * (at your option) any later version.\n *\n * This program is distributed in the hope that it will be useful,\n * but WITHOUT ANY WARRANTY; without even the implied warranty of\n * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\n * GNU General Public License for more details.\n *\n * You should have received a copy of the GNU General Public License\n * along with this program; if not, write to the Free Software\n * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA\n */\n\n/* Set the following three defines to your needs */\n\n#ifndef SDK_PWM_PERIOD_COMPAT_MODE\n  #define SDK_PWM_PERIOD_COMPAT_MODE 0\n#endif\n#ifndef PWM_MAX_CHANNELS\n  #define PWM_MAX_CHANNELS 8\n#endif\n#define PWM_DEBUG 0\n#define PWM_USE_NMI 0\n\n/* no user servicable parts beyond this point */\n\n#define PWM_MAX_TICKS 0x7fffff\n#if SDK_PWM_PERIOD_COMPAT_MODE\n#define PWM_PERIOD_TO_TICKS(x) (x * 0.2)\n#define PWM_DUTY_TO_TICKS(x) (x * 5)\n#define PWM_MAX_DUTY (PWM_MAX_TICKS * 0.2)\n#define PWM_MAX_PERIOD (PWM_MAX_TICKS * 5)\n#else\n#define PWM_PERIOD_TO_TICKS(x) (x)\n#define PWM_DUTY_TO_TICKS(x) (x)\n#define PWM_MAX_DUTY PWM_MAX_TICKS\n#define PWM_MAX_PERIOD PWM_MAX_TICKS\n#endif\n\n#include <c_types.h>\n#include <pwm.h>\n#include <eagle_soc.h>\n#include <ets_sys.h>\n\n// from SDK hw_timer.c\n#define TIMER1_DIVIDE_BY_16             0x0004\n#define TIMER1_ENABLE_TIMER             0x0080\n\nstruct pwm_phase {\n\tuint32_t ticks;    ///< delay until next phase, in 200ns units\n\tuint16_t on_mask;  ///< GPIO mask to switch on\n\tuint16_t off_mask; ///< GPIO mask to switch off\n};\n\n/* Three sets of PWM phases, the active one, the one used\n * starting with the next cycle, and the one updated\n * by pwm_start. After the update pwm_next_set\n * is set to the last updated set. pwm_current_set is set to\n * pwm_next_set from the interrupt routine during the first\n * pwm phase\n */\ntypedef struct pwm_phase (pwm_phase_array)[PWM_MAX_CHANNELS + 2];\nstatic pwm_phase_array pwm_phases[3];\nstatic struct {\n\tstruct pwm_phase* next_set;\n\tstruct pwm_phase* current_set;\n\tuint8_t current_phase;\n} pwm_state;\n\nstatic uint32_t pwm_period;\nstatic uint32_t pwm_period_ticks;\nstatic uint32_t pwm_duty[PWM_MAX_CHANNELS];\nstatic uint16_t gpio_mask[PWM_MAX_CHANNELS];\nstatic uint8_t pwm_channels;\n\n// 3-tuples of MUX_REGISTER, MUX_VALUE and GPIO number\ntypedef uint32_t (pin_info_type)[3];\n\nstruct gpio_regs {\n\tuint32_t out;         /* 0x60000300 */\n\tuint32_t out_w1ts;    /* 0x60000304 */\n\tuint32_t out_w1tc;    /* 0x60000308 */\n\tuint32_t enable;      /* 0x6000030C */\n\tuint32_t enable_w1ts; /* 0x60000310 */\n\tuint32_t enable_w1tc; /* 0x60000314 */\n\tuint32_t in;          /* 0x60000318 */\n\tuint32_t status;      /* 0x6000031C */\n\tuint32_t status_w1ts; /* 0x60000320 */\n\tuint32_t status_w1tc; /* 0x60000324 */\n};\nstatic struct gpio_regs* gpio = (struct gpio_regs*)(0x60000300);\n\nstruct timer_regs {\n\tuint32_t frc1_load;   /* 0x60000600 */\n\tuint32_t frc1_count;  /* 0x60000604 */\n\tuint32_t frc1_ctrl;   /* 0x60000608 */\n\tuint32_t frc1_int;    /* 0x6000060C */\n\tuint8_t  pad[16];\n\tuint32_t frc2_load;   /* 0x60000620 */\n\tuint32_t frc2_count;  /* 0x60000624 */\n\tuint32_t frc2_ctrl;   /* 0x60000628 */\n\tuint32_t frc2_int;    /* 0x6000062C */\n\tuint32_t frc2_alarm;  /* 0x60000630 */\n};\nstatic struct timer_regs* timer = (struct timer_regs*)(0x60000600);\n\nstatic void ICACHE_RAM_ATTR\npwm_intr_handler(void)\n{\n\tif ((pwm_state.current_set[pwm_state.current_phase].off_mask == 0) &&\n\t    (pwm_state.current_set[pwm_state.current_phase].on_mask == 0)) {\n\t\tpwm_state.current_set = pwm_state.next_set;\n\t\tpwm_state.current_phase = 0;\n\t}\n\n\tdo {\n\t\t// force write to GPIO registers on each loop\n\t\tasm volatile (\"\" : : : \"memory\");\n\n\t\tgpio->out_w1ts = (uint32_t)(pwm_state.current_set[pwm_state.current_phase].on_mask);\n\t\tgpio->out_w1tc = (uint32_t)(pwm_state.current_set[pwm_state.current_phase].off_mask);\n\n\t\tuint32_t ticks = pwm_state.current_set[pwm_state.current_phase].ticks;\n\n\t\tpwm_state.current_phase++;\n\n\t\tif (ticks) {\n\t\t\tif (ticks >= 16) {\n\t\t\t\t// constant interrupt overhead\n\t\t\t\tticks -= 9;\n\t\t\t\ttimer->frc1_int &= ~FRC1_INT_CLR_MASK;\n\t\t\t\tWRITE_PERI_REG(&timer->frc1_load, ticks);\n\t\t\t\treturn;\n\t\t\t}\n\n\t\t\tticks *= 4;\n\t\t\tdo {\n\t\t\t\tticks -= 1;\n\t\t\t\t// stop compiler from optimizing delay loop to noop\n\t\t\t\tasm volatile (\"\" : : : \"memory\");\n\t\t\t} while (ticks > 0);\n\t\t}\n\n\t} while (1);\n}\n\n/**\n * period: initial period (base unit 1us OR 200ns)\n * duty: array of initial duty values, may be NULL, may be freed after pwm_init\n * pwm_channel_num: number of channels to use\n * pin_info_list: array of pin_info\n */\nvoid ICACHE_FLASH_ATTR\npwm_init(uint32_t period, uint32_t *duty, uint32_t pwm_channel_num,\n              uint32_t (*pin_info_list)[3])\n{\n\tint i, j, n;\n\n\tpwm_channels = pwm_channel_num;\n\tif (pwm_channels > PWM_MAX_CHANNELS)\n\t\tpwm_channels = PWM_MAX_CHANNELS;\n\n\tfor (i = 0; i < 3; i++) {\n\t\tfor (j = 0; j < (PWM_MAX_CHANNELS + 2); j++) {\n\t\t\tpwm_phases[i][j].ticks = 0;\n\t\t\tpwm_phases[i][j].on_mask = 0;\n\t\t\tpwm_phases[i][j].off_mask = 0;\n\t\t}\n\t}\n\tpwm_state.current_set = pwm_state.next_set = 0;\n\tpwm_state.current_phase = 0;\n\n\tuint32_t all = 0;\n\t// PIN info: MUX-Register, Mux-Setting, PIN-Nr\n\tfor (n = 0; n < pwm_channels; n++) {\n\t\tpin_info_type* pin_info = &pin_info_list[n];\n\t\tPIN_FUNC_SELECT((*pin_info)[0], (*pin_info)[1]);\n\t\tgpio_mask[n] = 1 << (*pin_info)[2];\n\t\tall |= 1 << (*pin_info)[2];\n\t\tif (duty)\n\t\t\tpwm_set_duty(duty[n], n);\n\t}\n\tGPIO_REG_WRITE(GPIO_OUT_W1TC_ADDRESS, all);\n\tGPIO_REG_WRITE(GPIO_ENABLE_W1TS_ADDRESS, all);\n\n\tpwm_set_period(period);\n\n#if PWM_USE_NMI\n\tETS_FRC_TIMER1_NMI_INTR_ATTACH(pwm_intr_handler);\n#else\n\tETS_FRC_TIMER1_INTR_ATTACH(pwm_intr_handler, NULL);\n#endif\n\tTM1_EDGE_INT_ENABLE();\n\n\ttimer->frc1_int &= ~FRC1_INT_CLR_MASK;\n\ttimer->frc1_ctrl = 0;\n\n\tpwm_start();\n}\n\n__attribute__ ((noinline))\nstatic uint8_t ICACHE_FLASH_ATTR\n_pwm_phases_prep(struct pwm_phase* pwm)\n{\n\tuint8_t n, phases;\n\n\tuint16_t off_mask = 0;\n\tfor (n = 0; n < pwm_channels + 2; n++) {\n\t\tpwm[n].ticks = 0;\n\t\tpwm[n].on_mask = 0;\n\t\tpwm[n].off_mask = 0;\n\t}\n\tphases = 1;\n\tfor (n = 0; n < pwm_channels; n++) {\n\t\tuint32_t ticks = PWM_DUTY_TO_TICKS(pwm_duty[n]);\n\t\tif (ticks == 0) {\n\t\t\tpwm[0].off_mask |= gpio_mask[n];\n\t\t} else if (ticks >= pwm_period_ticks) {\n\t\t\tpwm[0].on_mask |= gpio_mask[n];\n\t\t} else {\n\t\t\tif (ticks < (pwm_period_ticks/2)) {\n\t\t\t\tpwm[phases].ticks = ticks;\n\t\t\t\tpwm[0].on_mask |= gpio_mask[n];\n\t\t\t\tpwm[phases].off_mask = gpio_mask[n];\n\t\t\t} else {\n\t\t\t\tpwm[phases].ticks = pwm_period_ticks - ticks;\n\t\t\t\tpwm[phases].on_mask = gpio_mask[n];\n\t\t\t\tpwm[0].off_mask |= gpio_mask[n];\n\t\t\t}\n\t\t\tphases++;\n\t\t}\n\t}\n\tpwm[phases].ticks = pwm_period_ticks;\n\n\t// bubble sort, lowest to hightest duty\n\tn = 2;\n\twhile (n < phases) {\n\t\tif (pwm[n].ticks < pwm[n - 1].ticks) {\n\t\t\tstruct pwm_phase t = pwm[n];\n\t\t\tpwm[n] = pwm[n - 1];\n\t\t\tpwm[n - 1] = t;\n\t\t\tif (n > 2)\n\t\t\t\tn--;\n\t\t} else {\n\t\t\tn++;\n\t\t}\n\t}\n\n#if PWM_DEBUG\n        int t = 0;\n\tfor (t = 0; t <= phases; t++) {\n\t\tets_printf(\"%d @%d:   %04x %04x\\n\", t, pwm[t].ticks, pwm[t].on_mask, pwm[t].off_mask);\n\t}\n#endif\n\n\t// shift left to align right edge;\n\tuint8_t l = 0, r = 1;\n\twhile (r <= phases) {\n\t\tuint32_t diff = pwm[r].ticks - pwm[l].ticks;\n\t\tif (diff && (diff <= 16)) {\n\t\t\tuint16_t mask = pwm[r].on_mask | pwm[r].off_mask;\n\t\t\tpwm[l].off_mask ^= pwm[r].off_mask;\n\t\t\tpwm[l].on_mask ^= pwm[r].on_mask;\n\t\t\tpwm[0].off_mask ^= pwm[r].on_mask;\n\t\t\tpwm[0].on_mask ^= pwm[r].off_mask;\n\t\t\tpwm[r].ticks = pwm_period_ticks - diff;\n\t\t\tpwm[r].on_mask ^= mask;\n\t\t\tpwm[r].off_mask ^= mask;\n\t\t} else {\n\t\t\tl = r;\n\t\t}\n\t\tr++;\n\t}\n\n#if PWM_DEBUG\n\tfor (t = 0; t <= phases; t++) {\n\t\tets_printf(\"%d @%d:   %04x %04x\\n\", t, pwm[t].ticks, pwm[t].on_mask, pwm[t].off_mask);\n\t}\n#endif\n\n\t// sort again\n\tn = 2;\n\twhile (n <= phases) {\n\t\tif (pwm[n].ticks < pwm[n - 1].ticks) {\n\t\t\tstruct pwm_phase t = pwm[n];\n\t\t\tpwm[n] = pwm[n - 1];\n\t\t\tpwm[n - 1] = t;\n\t\t\tif (n > 2)\n\t\t\t\tn--;\n\t\t} else {\n\t\t\tn++;\n\t\t}\n\t}\n\n\t// merge same duty\n\tl = 0, r = 1;\n\twhile (r <= phases) {\n\t\tif (pwm[r].ticks == pwm[l].ticks) {\n\t\t\tpwm[l].off_mask |= pwm[r].off_mask;\n\t\t\tpwm[l].on_mask |= pwm[r].on_mask;\n\t\t\tpwm[r].on_mask = 0;\n\t\t\tpwm[r].off_mask = 0;\n\t\t} else {\n\t\t\tl++;\n\t\t\tif (l != r) {\n\t\t\t\tstruct pwm_phase t = pwm[l];\n\t\t\t\tpwm[l] = pwm[r];\n\t\t\t\tpwm[r] = t;\n\t\t\t}\n\t\t}\n\t\tr++;\n\t}\n\tphases = l;\n\n#if PWM_DEBUG\n\tfor (t = 0; t <= phases; t++) {\n\t\tets_printf(\"%d @%d:   %04x %04x\\n\", t, pwm[t].ticks, pwm[t].on_mask, pwm[t].off_mask);\n\t}\n#endif\n\n\t// transform absolute end time to phase durations\n\tfor (n = 0; n < phases; n++) {\n\t\tpwm[n].ticks =\n\t\t\tpwm[n + 1].ticks - pwm[n].ticks;\n\t\t// subtract common overhead\n\t\tpwm[n].ticks--;\n\t}\n\tpwm[phases].ticks = 0;\n\n\t// do a cyclic shift if last phase is short\n\tif (pwm[phases - 1].ticks < 16) {\n\t\tfor (n = 0; n < phases - 1; n++) {\n\t\t\tstruct pwm_phase t = pwm[n];\n\t\t\tpwm[n] = pwm[n + 1];\n\t\t\tpwm[n + 1] = t;\n\t\t}\n\t}\n\n#if PWM_DEBUG\n\tfor (t = 0; t <= phases; t++) {\n\t\tets_printf(\"%d +%d:   %04x %04x\\n\", t, pwm[t].ticks, pwm[t].on_mask, pwm[t].off_mask);\n\t}\n\tets_printf(\"\\n\");\n#endif\n\n\treturn phases;\n}\n\nvoid ICACHE_FLASH_ATTR\npwm_start(void)\n{\n\tpwm_phase_array* pwm = &pwm_phases[0];\n\n\tif ((*pwm == pwm_state.next_set) ||\n\t    (*pwm == pwm_state.current_set))\n\t\tpwm++;\n\tif ((*pwm == pwm_state.next_set) ||\n\t    (*pwm == pwm_state.current_set))\n\t\tpwm++;\n\n\tuint8_t phases = _pwm_phases_prep(*pwm);\n\n        // all with 0% / 100% duty - stop timer\n\tif (phases == 1) {\n\t\tif (pwm_state.next_set) {\n#if PWM_DEBUG\n\t\t\tets_printf(\"PWM stop\\n\");\n#endif\n\t\t\ttimer->frc1_ctrl = 0;\n\t\t\tETS_FRC1_INTR_DISABLE();\n\t\t}\n\t\tpwm_state.next_set = NULL;\n\n\t\tGPIO_REG_WRITE(GPIO_OUT_W1TS_ADDRESS, (*pwm)[0].on_mask);\n\t\tGPIO_REG_WRITE(GPIO_OUT_W1TC_ADDRESS, (*pwm)[0].off_mask);\n\n\t\treturn;\n\t}\n\n\t// start if not running\n\tif (!pwm_state.next_set) {\n#if PWM_DEBUG\n\t\tets_printf(\"PWM start\\n\");\n#endif\n\t\tpwm_state.current_set = pwm_state.next_set = *pwm;\n\t\tpwm_state.current_phase = phases - 1;\n\t\tETS_FRC1_INTR_ENABLE();\n\t\tRTC_REG_WRITE(FRC1_LOAD_ADDRESS, 0);\n\t\ttimer->frc1_ctrl = TIMER1_DIVIDE_BY_16 | TIMER1_ENABLE_TIMER;\n\t\treturn;\n\t}\n\n\tpwm_state.next_set = *pwm;\n}\n\nvoid ICACHE_FLASH_ATTR\npwm_set_duty(uint32_t duty, uint8_t channel)\n{\n\tif (channel > PWM_MAX_CHANNELS)\n\t\treturn;\n\n\tif (duty > PWM_MAX_DUTY)\n\t\tduty = PWM_MAX_DUTY;\n\n\tpwm_duty[channel] = duty;\n}\n\nuint32_t ICACHE_FLASH_ATTR\npwm_get_duty(uint8_t channel)\n{\n\tif (channel > PWM_MAX_CHANNELS)\n\t\treturn 0;\n\treturn pwm_duty[channel];\n}\n\nvoid ICACHE_FLASH_ATTR\npwm_set_period(uint32_t period)\n{\n\tpwm_period = period;\n\n\tif (pwm_period > PWM_MAX_PERIOD)\n\t\tpwm_period = PWM_MAX_PERIOD;\n\n\tpwm_period_ticks = PWM_PERIOD_TO_TICKS(period);\n}\n\nuint32_t ICACHE_FLASH_ATTR\npwm_get_period(void)\n{\n\treturn pwm_period;\n}\n\nuint32_t ICACHE_FLASH_ATTR\nget_pwm_version(void)\n{\n\treturn 1;\n}\n\nvoid ICACHE_FLASH_ATTR\nset_pwm_debug_en(uint8_t print_en)\n{\n\t(void) print_en;\n}\n\n"
  }
]