sim900.cpp

/*
    sim900.cpp
    A library for SeeedStudio seeeduino GPRS shield

    Copyright (c) 2015 seeed technology inc.
    Website    : www.seeed.cc
    Author     : lawliet zou
    Create Time: April 2015
    Change Log :

    The MIT License (MIT)

    Permission is hereby granted, free of charge, to any person obtaining a copy
    of this software and associated documentation files (the "Software"), to deal
    in the Software without restriction, including without limitation the rights
    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
    copies of the Software, and to permit persons to whom the Software is
    furnished to do so, subject to the following conditions:

    The above copyright notice and this permission notice shall be included in
    all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    THE SOFTWARE.
*/

#include "sim900.h"


SoftwareSerial* serialSIM900 = NULL;

void  sim900_init(void* uart_device, uint32_t baud) {
    serialSIM900 = (SoftwareSerial*)uart_device;
    serialSIM900->begin(baud);
}

int sim900_check_readable() {
    return serialSIM900->available();
}

int sim900_wait_readable(int wait_time) {
    unsigned long timerStart;
    int dataLen = 0;
    timerStart = millis();
    while ((unsigned long)(millis() - timerStart) < wait_time * 1000UL) {
        delay(500);
        dataLen = sim900_check_readable();
        if (dataLen > 0) {
            break;
        }
    }
    return dataLen;
}

void sim900_flush_serial() {
    while (sim900_check_readable()) {
        serialSIM900->read();
    }
}

void sim900_read_buffer(char* buffer, int count, unsigned int timeout, unsigned int chartimeout) {
    int i = 0;
    unsigned long timerStart, prevChar;
    timerStart = millis();
    prevChar = 0;
    while (1) {
        while (sim900_check_readable()) {
            char c = serialSIM900->read();
            prevChar = millis();
            buffer[i++] = c;
            DEBUG("-"); DEBUG(c);
            if (i >= count) {
                break;
            }
        }
        if (i >= count) {
            break;
        }
        if ((unsigned long)(millis() - timerStart) > timeout * 1000UL) {
            break;
        }
        //If interchar Timeout => return FALSE. So we can return sooner from this function. Not DO it if we dont recieve at least one char (prevChar <> 0)
        if (((unsigned long)(millis() - prevChar) > chartimeout) && (prevChar != 0)) {
            break;
        }
    }
}

char* sim900_read_string_until(char* buffer, uint16_t count, const char* pattern, unsigned int timeout,
                               unsigned int chartimeout) {
    uint16_t i = 0;
    uint8_t sum = 0;
    uint8_t len = strlen(pattern);
    char* foundPtr = NULL;
    unsigned long timerStart, prevChar;

    timerStart = millis();
    prevChar = 0;
    while (1) {
        if (serialSIM900->available()) {
            char c = serialSIM900->read();
            DEBUG(c);
            prevChar = millis();
            buffer[i++] = c;

            sum = (c == pattern[sum]) ? sum + 1 : 0;

            if (sum == len) {
                foundPtr = &(buffer[i - len]);
                break;
            }
        }

        if (i >= count) {
            break;
        }

        if ((unsigned long)(millis() - timerStart) > timeout * 1000UL) {
            break;
        }
        //If interchar Timeout => return FALSE. So we can return sooner from this function. Not DO it if we dont recieve at least one char (prevChar <> 0)
        if (((unsigned long)(millis() - prevChar) > chartimeout) && (prevChar != 0)) {
            break;
        }
    }
    DEBUG("\n\n");

    return foundPtr;
}


void sim900_clean_buffer(char* buffer, int count) {
    for (int i = 0; i < count; i++) {
        buffer[i] = '\0';
    }
}

void sim900_send_byte(uint8_t data) {
    serialSIM900->write(data);
    DEBUG((char)data);
}


void sim900_send_char(const char c) {
    serialSIM900->write(c);
    DEBUG(c);
}

void sim900_send_cmd(const char* cmd) {
    for (uint16_t i = 0; i < strlen(cmd); i++) {
        sim900_send_byte(cmd[i]);
    }
}

void sim900_send_cmd(const __FlashStringHelper* cmd) {
    int i = 0;
    const char* ptr = (const char*) cmd;
    while (pgm_read_byte(ptr + i) != 0x00) {
        sim900_send_byte(pgm_read_byte(ptr + i++));
    }
}

void sim900_send_cmd_P(const char* cmd) {
    while (pgm_read_byte(cmd) != 0x00) {
        sim900_send_byte(pgm_read_byte(cmd++));
    }
}

boolean sim900_send_AT(void) {
    return sim900_check_with_cmd(F("AT\r\n"), "OK", CMD);
}

void sim900_send_End_Mark(void) {
    sim900_send_byte((char)26);
}

boolean sim900_wait_for_resp(const char* resp, DataType type, unsigned int timeout, unsigned int chartimeout) {
    int len = strlen(resp);
    int sum = 0;
    unsigned long timerStart, prevChar;    //prevChar is the time when the previous Char has been read.
    timerStart = millis();
    prevChar = 0;
    while (1) {
        if (sim900_check_readable()) {
            char c = serialSIM900->read();
            DEBUG("-");
            DEBUG(c);
            prevChar = millis();
            sum = (c == resp[sum]) ? sum + 1 : 0;
            if (sum == len) {
                break;
            }
        }
        if ((unsigned long)(millis() - timerStart) > timeout * 1000UL) {
            return false;
        }
        //If interchar Timeout => return FALSE. So we can return sooner from this function.
        if (((unsigned long)(millis() - prevChar) > chartimeout) && (prevChar != 0)) {
            return false;
        }

    }
    //If is a CMD, we will finish to read buffer.
    if (type == CMD) {
        sim900_flush_serial();
    }
    return true;
}


boolean sim900_check_with_cmd(const char* cmd, const char* resp, DataType type, unsigned int timeout,
                              unsigned int chartimeout) {
    sim900_send_cmd(cmd);
    return sim900_wait_for_resp(resp, type, timeout, chartimeout);
}

//HACERR que tambien la respuesta pueda ser FLASH STRING
boolean sim900_check_with_cmd(const __FlashStringHelper* cmd, const char* resp, DataType type, unsigned int timeout,
                              unsigned int chartimeout) {
    sim900_send_cmd(cmd);
    return sim900_wait_for_resp(resp, type, timeout, chartimeout);
}

void sim900_AT_bypass() {
    if (serialSIM900->available()) {
        Serial.write(serialSIM900->read());
    }
    if (Serial.available()) {
        serialSIM900->write(Serial.read());
    }
}