Parser for AT commands and similar protocols

Dependencies:   BufferedSerial

Dependents:   ESP8266 Final_Project_2 Final_Project CHEN_Final_Project

Files at this revision

API Documentation at this revision

Comitter:
Christopher Haster
Date:
Thu Feb 18 15:59:15 2016 -0600
Parent:
11:fd406d4c4227
Child:
13:46a18ad08efc
Commit message:
Removed carriage returns

Changed in this revision

ATParser.cpp Show annotated file Show diff for this revision Revisions of this file
ATParser.h Show annotated file Show diff for this revision Revisions of this file
--- a/ATParser.cpp	Mon Dec 28 05:37:44 2015 +0000
+++ b/ATParser.cpp	Thu Feb 18 15:59:15 2016 -0600
@@ -1,310 +1,310 @@
-/* Copyright (c) 2015 ARM Limited
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- * @section DESCRIPTION
- *
- * Parser for the AT command syntax
- *
- */
-
-#include "ATParser.h"
-#include "mbed_debug.h"
-
-
-// getc/putc handling with timeouts
-int ATParser::putc(char c)
-{
-    Timer timer;
-    timer.start();
-
-    while (true) {
-        if (_serial->writeable()) {
-            return _serial->putc(c);
-        }
-        if (timer.read_ms() > _timeout) {
-            return -1;
-        }
-    }
-}
-
-int ATParser::getc()
-{
-    Timer timer;
-    timer.start();
-
-    while (true) {
-        if (_serial->readable()) {
-            return _serial->getc();
-        }
-        if (timer.read_ms() > _timeout) {
-            return -1;
-        }
-    }
-}
-
-void ATParser::flush()
-{
-    while (_serial->readable()) {
-        _serial->getc();
-    }
-}
-
-
-// read/write handling with timeouts
-int ATParser::write(const char *data, int size)
-{
-    int i = 0;
-    for ( ; i < size; i++) {
-        if (putc(data[i]) < 0) {
-            return -1;
-        }
-    }
-    return i;
-}
-
-int ATParser::read(char *data, int size)
-{
-    int i = 0;
-    for ( ; i < size; i++) {
-        int c = getc();
-        if (c < 0) {
-            return -1;
-        }
-        data[i] = c;
-    }
-    return i;
-}
-
-
-// printf/scanf handling
-int ATParser::vprintf(const char *format, va_list args)
-{
-    if (vsprintf(_buffer, format, args) < 0) {
-        return false;
-    }
-    int i = 0;
-    for ( ; _buffer[i]; i++) {
-        if (putc(_buffer[i]) < 0) {
-            return -1;
-        }
-    }
-    return i;
-}
-
-int ATParser::vscanf(const char *format, va_list args)
-{
-    // Since format is const, we need to copy it into our buffer to
-    // add the line's null terminator and clobber value-matches with asterisks.
-    //
-    // We just use the beginning of the buffer to avoid unnecessary allocations.
-    int i = 0;
-    int offset = 0;
-
-    while (format[i]) {
-        if (format[i] == '%' && format[i+1] != '%' && format[i+1] != '*') {
-            _buffer[offset++] = '%';
-            _buffer[offset++] = '*';
-            i++;
-        } else {
-            _buffer[offset++] = format[i++];
-        }
-    }
-
-    // Scanf has very poor support for catching errors
-    // fortunately, we can abuse the %n specifier to determine
-    // if the entire string was matched.
-    _buffer[offset++] = '%';
-    _buffer[offset++] = 'n';
-    _buffer[offset++] = 0;
-
-    // To workaround scanf's lack of error reporting, we actually
-    // make two passes. One checks the validity with the modified
-    // format string that only stores the matched characters (%n).
-    // The other reads in the actual matched values.
-    //
-    // We keep trying the match until we succeed or some other error
-    // derails us.
-    int j = 0;
-
-    while (true) {
-        // Ran out of space
-        if (j+1 >= _buffer_size - offset) {
-            return false;
-        }
-        // Recieve next character
-        int c = getc();
-        if (c < 0) {
-            return -1;
-        }
-        _buffer[offset + j++] = c;
-        _buffer[offset + j] = 0;
-
-        // Check for match
-        int count = -1;
-        sscanf(_buffer+offset, _buffer, &count);
-
-        // We only succeed if all characters in the response are matched
-        if (count == j) {
-            // Store the found results
-            vsscanf(_buffer+offset, format, args);
-            return j;
-        }
-    }
-}
-
-
-// Command parsing with line handling
-bool ATParser::vsend(const char *command, va_list args)
-{
-    // Create and send command
-    if (vsprintf(_buffer, command, args) < 0) {
-        return false;
-    }
-    for (int i = 0; _buffer[i]; i++) {
-        if (putc(_buffer[i]) < 0) {
-            return false;
-        }
-    }
-
-    // Finish with newline
-    for (int i = 0; _delimiter[i]; i++) {
-        if (putc(_delimiter[i]) < 0) {
-            return false;
-        }
-    }
-
-    debug_if(dbg_on, "AT> %s\r\n", _buffer);
-    return true;
-}
-
-bool ATParser::vrecv(const char *response, va_list args)
-{
-    // Iterate through each line in the expected response
-    while (response[0]) {
-        // Since response is const, we need to copy it into our buffer to
-        // add the line's null terminator and clobber value-matches with asterisks.
-        //
-        // We just use the beginning of the buffer to avoid unnecessary allocations.
-        int i = 0;
-        int offset = 0;
-
-        while (response[i]) {
-            if (memcmp(&response[i+1-_delim_size], _delimiter, _delim_size) == 0) {
-                i++;
-                break;
-            } else if (response[i] == '%' && response[i+1] != '%' && response[i+1] != '*') {
-                _buffer[offset++] = '%';
-                _buffer[offset++] = '*';
-                i++;
-            } else {
-                _buffer[offset++] = response[i++];
-            }
-        }
-
-        // Scanf has very poor support for catching errors
-        // fortunately, we can abuse the %n specifier to determine
-        // if the entire string was matched.
-        _buffer[offset++] = '%';
-        _buffer[offset++] = 'n';
-        _buffer[offset++] = 0;
-
-        // To workaround scanf's lack of error reporting, we actually
-        // make two passes. One checks the validity with the modified
-        // format string that only stores the matched characters (%n).
-        // The other reads in the actual matched values.
-        //
-        // We keep trying the match until we succeed or some other error
-        // derails us.
-        int j = 0;
-
-        while (true) {
-            // Ran out of space
-            if (j+1 >= _buffer_size - offset) {
-                return false;
-            }
-            // Recieve next character
-            int c = getc();
-            if (c < 0) {
-                return false;
-            }
-            _buffer[offset + j++] = c;
-            _buffer[offset + j] = 0;
-
-            // Check for match
-            int count = -1;
-            sscanf(_buffer+offset, _buffer, &count);
-
-            // We only succeed if all characters in the response are matched
-            if (count == j) {
-                debug_if(dbg_on, "AT= %s\r\n", _buffer+offset);
-                // Reuse the front end of the buffer
-                memcpy(_buffer, response, i);
-                _buffer[i] = 0;
-
-                // Store the found results
-                vsscanf(_buffer+offset, _buffer, args);
-
-                // Jump to next line and continue parsing
-                response += i;
-                break;
-            }
-
-            // Clear the buffer when we hit a newline
-            if (strcmp(&_buffer[offset + j-_delim_size], _delimiter) == 0) {
-                debug_if(dbg_on, "AT< %s", _buffer+offset);
-                j = 0;
-            }
-        }
-    }
-
-    return true;
-}
-
-
-// Mapping to vararg functions
-int ATParser::printf(const char *format, ...)
-{
-    va_list args;
-    va_start(args, format);
-    int res = vprintf(format, args);
-    va_end(args);
-    return res;
-}
-
-int ATParser::scanf(const char *format, ...)
-{
-    va_list args;
-    va_start(args, format);
-    int res = vscanf(format, args);
-    va_end(args);
-    return res;
-}
-
-bool ATParser::send(const char *command, ...)
-{
-    va_list args;
-    va_start(args, command);
-    bool res = vsend(command, args);
-    va_end(args);
-    return res;
-}
-
-bool ATParser::recv(const char *response, ...)
-{
-    va_list args;
-    va_start(args, response);
-    bool res = vrecv(response, args);
-    va_end(args);
-    return res;
-}
+/* Copyright (c) 2015 ARM Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * @section DESCRIPTION
+ *
+ * Parser for the AT command syntax
+ *
+ */
+
+#include "ATParser.h"
+#include "mbed_debug.h"
+
+
+// getc/putc handling with timeouts
+int ATParser::putc(char c)
+{
+    Timer timer;
+    timer.start();
+
+    while (true) {
+        if (_serial->writeable()) {
+            return _serial->putc(c);
+        }
+        if (timer.read_ms() > _timeout) {
+            return -1;
+        }
+    }
+}
+
+int ATParser::getc()
+{
+    Timer timer;
+    timer.start();
+
+    while (true) {
+        if (_serial->readable()) {
+            return _serial->getc();
+        }
+        if (timer.read_ms() > _timeout) {
+            return -1;
+        }
+    }
+}
+
+void ATParser::flush()
+{
+    while (_serial->readable()) {
+        _serial->getc();
+    }
+}
+
+
+// read/write handling with timeouts
+int ATParser::write(const char *data, int size)
+{
+    int i = 0;
+    for ( ; i < size; i++) {
+        if (putc(data[i]) < 0) {
+            return -1;
+        }
+    }
+    return i;
+}
+
+int ATParser::read(char *data, int size)
+{
+    int i = 0;
+    for ( ; i < size; i++) {
+        int c = getc();
+        if (c < 0) {
+            return -1;
+        }
+        data[i] = c;
+    }
+    return i;
+}
+
+
+// printf/scanf handling
+int ATParser::vprintf(const char *format, va_list args)
+{
+    if (vsprintf(_buffer, format, args) < 0) {
+        return false;
+    }
+    int i = 0;
+    for ( ; _buffer[i]; i++) {
+        if (putc(_buffer[i]) < 0) {
+            return -1;
+        }
+    }
+    return i;
+}
+
+int ATParser::vscanf(const char *format, va_list args)
+{
+    // Since format is const, we need to copy it into our buffer to
+    // add the line's null terminator and clobber value-matches with asterisks.
+    //
+    // We just use the beginning of the buffer to avoid unnecessary allocations.
+    int i = 0;
+    int offset = 0;
+
+    while (format[i]) {
+        if (format[i] == '%' && format[i+1] != '%' && format[i+1] != '*') {
+            _buffer[offset++] = '%';
+            _buffer[offset++] = '*';
+            i++;
+        } else {
+            _buffer[offset++] = format[i++];
+        }
+    }
+
+    // Scanf has very poor support for catching errors
+    // fortunately, we can abuse the %n specifier to determine
+    // if the entire string was matched.
+    _buffer[offset++] = '%';
+    _buffer[offset++] = 'n';
+    _buffer[offset++] = 0;
+
+    // To workaround scanf's lack of error reporting, we actually
+    // make two passes. One checks the validity with the modified
+    // format string that only stores the matched characters (%n).
+    // The other reads in the actual matched values.
+    //
+    // We keep trying the match until we succeed or some other error
+    // derails us.
+    int j = 0;
+
+    while (true) {
+        // Ran out of space
+        if (j+1 >= _buffer_size - offset) {
+            return false;
+        }
+        // Recieve next character
+        int c = getc();
+        if (c < 0) {
+            return -1;
+        }
+        _buffer[offset + j++] = c;
+        _buffer[offset + j] = 0;
+
+        // Check for match
+        int count = -1;
+        sscanf(_buffer+offset, _buffer, &count);
+
+        // We only succeed if all characters in the response are matched
+        if (count == j) {
+            // Store the found results
+            vsscanf(_buffer+offset, format, args);
+            return j;
+        }
+    }
+}
+
+
+// Command parsing with line handling
+bool ATParser::vsend(const char *command, va_list args)
+{
+    // Create and send command
+    if (vsprintf(_buffer, command, args) < 0) {
+        return false;
+    }
+    for (int i = 0; _buffer[i]; i++) {
+        if (putc(_buffer[i]) < 0) {
+            return false;
+        }
+    }
+
+    // Finish with newline
+    for (int i = 0; _delimiter[i]; i++) {
+        if (putc(_delimiter[i]) < 0) {
+            return false;
+        }
+    }
+
+    debug_if(dbg_on, "AT> %s\r\n", _buffer);
+    return true;
+}
+
+bool ATParser::vrecv(const char *response, va_list args)
+{
+    // Iterate through each line in the expected response
+    while (response[0]) {
+        // Since response is const, we need to copy it into our buffer to
+        // add the line's null terminator and clobber value-matches with asterisks.
+        //
+        // We just use the beginning of the buffer to avoid unnecessary allocations.
+        int i = 0;
+        int offset = 0;
+
+        while (response[i]) {
+            if (memcmp(&response[i+1-_delim_size], _delimiter, _delim_size) == 0) {
+                i++;
+                break;
+            } else if (response[i] == '%' && response[i+1] != '%' && response[i+1] != '*') {
+                _buffer[offset++] = '%';
+                _buffer[offset++] = '*';
+                i++;
+            } else {
+                _buffer[offset++] = response[i++];
+            }
+        }
+
+        // Scanf has very poor support for catching errors
+        // fortunately, we can abuse the %n specifier to determine
+        // if the entire string was matched.
+        _buffer[offset++] = '%';
+        _buffer[offset++] = 'n';
+        _buffer[offset++] = 0;
+
+        // To workaround scanf's lack of error reporting, we actually
+        // make two passes. One checks the validity with the modified
+        // format string that only stores the matched characters (%n).
+        // The other reads in the actual matched values.
+        //
+        // We keep trying the match until we succeed or some other error
+        // derails us.
+        int j = 0;
+
+        while (true) {
+            // Ran out of space
+            if (j+1 >= _buffer_size - offset) {
+                return false;
+            }
+            // Recieve next character
+            int c = getc();
+            if (c < 0) {
+                return false;
+            }
+            _buffer[offset + j++] = c;
+            _buffer[offset + j] = 0;
+
+            // Check for match
+            int count = -1;
+            sscanf(_buffer+offset, _buffer, &count);
+
+            // We only succeed if all characters in the response are matched
+            if (count == j) {
+                debug_if(dbg_on, "AT= %s\r\n", _buffer+offset);
+                // Reuse the front end of the buffer
+                memcpy(_buffer, response, i);
+                _buffer[i] = 0;
+
+                // Store the found results
+                vsscanf(_buffer+offset, _buffer, args);
+
+                // Jump to next line and continue parsing
+                response += i;
+                break;
+            }
+
+            // Clear the buffer when we hit a newline
+            if (strcmp(&_buffer[offset + j-_delim_size], _delimiter) == 0) {
+                debug_if(dbg_on, "AT< %s", _buffer+offset);
+                j = 0;
+            }
+        }
+    }
+
+    return true;
+}
+
+
+// Mapping to vararg functions
+int ATParser::printf(const char *format, ...)
+{
+    va_list args;
+    va_start(args, format);
+    int res = vprintf(format, args);
+    va_end(args);
+    return res;
+}
+
+int ATParser::scanf(const char *format, ...)
+{
+    va_list args;
+    va_start(args, format);
+    int res = vscanf(format, args);
+    va_end(args);
+    return res;
+}
+
+bool ATParser::send(const char *command, ...)
+{
+    va_list args;
+    va_start(args, command);
+    bool res = vsend(command, args);
+    va_end(args);
+    return res;
+}
+
+bool ATParser::recv(const char *response, ...)
+{
+    va_list args;
+    va_start(args, response);
+    bool res = vrecv(response, args);
+    va_end(args);
+    return res;
+}
--- a/ATParser.h	Mon Dec 28 05:37:44 2015 +0000
+++ b/ATParser.h	Thu Feb 18 15:59:15 2016 -0600
@@ -1,201 +1,201 @@
-/* Copyright (c) 2015 ARM Limited
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- * @section DESCRIPTION
- *
- * Parser for the AT command syntax
- *
- */
-
-#include "mbed.h"
-#include <cstdarg>
-#include "BufferedSerial.h"
-
-
-/**
-* Parser class for parsing AT commands
-*
-* Here are some examples:
-* @code
-* ATParser at = ATParser(serial, "\r\n");
-* int value;
-* char buffer[100];
-*
-* at.send("AT") && at.recv("OK");
-* at.send("AT+CWMODE=%d", 3) && at.recv("OK");
-* at.send("AT+CWMODE?") && at.recv("+CWMODE:%d\r\nOK", &value);
-* at.recv("+IPD,%d:", &value);
-* at.read(buffer, value);
-* at.recv("OK");
-* @endcode
-*/
-class ATParser
-{
-private:
-    // Serial information
-    BufferedSerial *_serial;
-    int _buffer_size;
-    char *_buffer;
-    int _timeout;
-
-    // Parsing information
-    const char *_delimiter;
-    int _delim_size;
-    bool dbg_on;
-
-public:
-    /**
-    * Constructor
-    *
-    * @param serial serial interface to use for AT commands
-    * @param buffer_size size of internal buffer for transaction
-    * @param timeout timeout of the connection
-    * @param delimiter string of characters to use as line delimiters
-    */
-    ATParser(BufferedSerial &serial, const char *delimiter = "\r\n", int buffer_size = 256, int timeout = 8000, bool debug = false) :
-        _serial(&serial),
-        _buffer_size(buffer_size) {
-        _buffer = new char[buffer_size];
-        setTimeout(timeout);
-        setDelimiter(delimiter);
-        debugOn(debug);
-    }
-
-    /**
-    * Destructor
-    */
-    ~ATParser() {
-        delete [] _buffer;
-    }
-
-    /**
-    * Allows timeout to be changed between commands
-    *
-    * @param timeout timeout of the connection
-    */
-    void setTimeout(int timeout) {
-        _timeout = timeout;
-    }
-
-    /**
-    * Sets string of characters to use as line delimiters
-    *
-    * @param delimiter string of characters to use as line delimiters
-    */
-    void setDelimiter(const char *delimiter) {
-        _delimiter = delimiter;
-        _delim_size = strlen(delimiter);
-    }
-    
-    /**
-    * Allows echo to be on or off
-    *
-    * @param echo 1 for echo and 0 turns it off
-    */
-    void debugOn(uint8_t on) {
-        dbg_on = (on) ? 1 : 0;
-    }
-
-    /**
-    * Sends an AT command
-    *
-    * Sends a formatted command using printf style formatting
-    * @see ::printf
-    *
-    * @param command printf-like format string of command to send which
-    *                is appended with the specified delimiter
-    * @param ... all printf-like arguments to insert into command
-    * @return true only if command is successfully sent
-    */
-    bool send(const char *command, ...);
-    bool vsend(const char *command, va_list args);
-
-    /**
-    * Recieve an AT response
-    *
-    * Recieves a formatted response using scanf style formatting
-    * @see ::scanf
-    *
-    * Responses are parsed line at a time using the specified delimiter.
-    * Any recieved data that does not match the response is ignored until
-    * a timeout occurs.
-    *
-    * @param response scanf-like format string of response to expect
-    * @param ... all scanf-like arguments to extract from response
-    * @return true only if response is successfully matched
-    */
-    bool recv(const char *response, ...);
-    bool vrecv(const char *response, va_list args);
-
-    /**
-    * Write a single byte to the underlying stream
-    *
-    * @param c The byte to write
-    * @return The byte that was written or -1 during a timeout
-    */
-    int putc(char c);
-
-    /**
-    * Get a single byte from the underlying stream
-    *
-    * @return The byte that was read or -1 during a timeout
-    */
-    int getc();
-
-    /**
-    * Write an array of bytes to the underlying stream
-    *
-    * @param data the array of bytes to write
-    * @param size number of bytes to write
-    * @return number of bytes written or -1 on failure
-    */
-    int write(const char *data, int size);
-
-    /**
-    * Read an array of bytes from the underlying stream
-    *
-    * @param data the destination for the read bytes
-    * @param size number of bytes to read
-    * @return number of bytes read or -1 on failure
-    */
-    int read(char *data, int size);
-
-    /**
-    * Direct printf to underlying stream
-    * @see ::printf
-    *
-    * @param format format string to pass to printf
-    * @param ... arguments to printf
-    * @return number of bytes written or -1 on failure
-    */
-    int printf(const char *format, ...);
-    int vprintf(const char *format, va_list args);
-
-    /**
-    * Direct scanf on underlying stream
-    * @see ::scanf
-    *
-    * @param format format string to pass to scanf
-    * @param ... arguments to scanf
-    * @return number of bytes read or -1 on failure
-    */
-    int scanf(const char *format, ...);
-    int vscanf(const char *format, va_list args);
-
-    /**
-    * Flushes the underlying stream
-    */
-    void flush();
-};
-
+/* Copyright (c) 2015 ARM Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * @section DESCRIPTION
+ *
+ * Parser for the AT command syntax
+ *
+ */
+
+#include "mbed.h"
+#include <cstdarg>
+#include "BufferedSerial.h"
+
+
+/**
+* Parser class for parsing AT commands
+*
+* Here are some examples:
+* @code
+* ATParser at = ATParser(serial, "\r\n");
+* int value;
+* char buffer[100];
+*
+* at.send("AT") && at.recv("OK");
+* at.send("AT+CWMODE=%d", 3) && at.recv("OK");
+* at.send("AT+CWMODE?") && at.recv("+CWMODE:%d\r\nOK", &value);
+* at.recv("+IPD,%d:", &value);
+* at.read(buffer, value);
+* at.recv("OK");
+* @endcode
+*/
+class ATParser
+{
+private:
+    // Serial information
+    BufferedSerial *_serial;
+    int _buffer_size;
+    char *_buffer;
+    int _timeout;
+
+    // Parsing information
+    const char *_delimiter;
+    int _delim_size;
+    bool dbg_on;
+
+public:
+    /**
+    * Constructor
+    *
+    * @param serial serial interface to use for AT commands
+    * @param buffer_size size of internal buffer for transaction
+    * @param timeout timeout of the connection
+    * @param delimiter string of characters to use as line delimiters
+    */
+    ATParser(BufferedSerial &serial, const char *delimiter = "\r\n", int buffer_size = 256, int timeout = 8000, bool debug = false) :
+        _serial(&serial),
+        _buffer_size(buffer_size) {
+        _buffer = new char[buffer_size];
+        setTimeout(timeout);
+        setDelimiter(delimiter);
+        debugOn(debug);
+    }
+
+    /**
+    * Destructor
+    */
+    ~ATParser() {
+        delete [] _buffer;
+    }
+
+    /**
+    * Allows timeout to be changed between commands
+    *
+    * @param timeout timeout of the connection
+    */
+    void setTimeout(int timeout) {
+        _timeout = timeout;
+    }
+
+    /**
+    * Sets string of characters to use as line delimiters
+    *
+    * @param delimiter string of characters to use as line delimiters
+    */
+    void setDelimiter(const char *delimiter) {
+        _delimiter = delimiter;
+        _delim_size = strlen(delimiter);
+    }
+    
+    /**
+    * Allows echo to be on or off
+    *
+    * @param echo 1 for echo and 0 turns it off
+    */
+    void debugOn(uint8_t on) {
+        dbg_on = (on) ? 1 : 0;
+    }
+
+    /**
+    * Sends an AT command
+    *
+    * Sends a formatted command using printf style formatting
+    * @see ::printf
+    *
+    * @param command printf-like format string of command to send which
+    *                is appended with the specified delimiter
+    * @param ... all printf-like arguments to insert into command
+    * @return true only if command is successfully sent
+    */
+    bool send(const char *command, ...);
+    bool vsend(const char *command, va_list args);
+
+    /**
+    * Recieve an AT response
+    *
+    * Recieves a formatted response using scanf style formatting
+    * @see ::scanf
+    *
+    * Responses are parsed line at a time using the specified delimiter.
+    * Any recieved data that does not match the response is ignored until
+    * a timeout occurs.
+    *
+    * @param response scanf-like format string of response to expect
+    * @param ... all scanf-like arguments to extract from response
+    * @return true only if response is successfully matched
+    */
+    bool recv(const char *response, ...);
+    bool vrecv(const char *response, va_list args);
+
+    /**
+    * Write a single byte to the underlying stream
+    *
+    * @param c The byte to write
+    * @return The byte that was written or -1 during a timeout
+    */
+    int putc(char c);
+
+    /**
+    * Get a single byte from the underlying stream
+    *
+    * @return The byte that was read or -1 during a timeout
+    */
+    int getc();
+
+    /**
+    * Write an array of bytes to the underlying stream
+    *
+    * @param data the array of bytes to write
+    * @param size number of bytes to write
+    * @return number of bytes written or -1 on failure
+    */
+    int write(const char *data, int size);
+
+    /**
+    * Read an array of bytes from the underlying stream
+    *
+    * @param data the destination for the read bytes
+    * @param size number of bytes to read
+    * @return number of bytes read or -1 on failure
+    */
+    int read(char *data, int size);
+
+    /**
+    * Direct printf to underlying stream
+    * @see ::printf
+    *
+    * @param format format string to pass to printf
+    * @param ... arguments to printf
+    * @return number of bytes written or -1 on failure
+    */
+    int printf(const char *format, ...);
+    int vprintf(const char *format, va_list args);
+
+    /**
+    * Direct scanf on underlying stream
+    * @see ::scanf
+    *
+    * @param format format string to pass to scanf
+    * @param ... arguments to scanf
+    * @return number of bytes read or -1 on failure
+    */
+    int scanf(const char *format, ...);
+    int vscanf(const char *format, va_list args);
+
+    /**
+    * Flushes the underlying stream
+    */
+    void flush();
+};
+