diff --git a/libraries/DataFlash/DataFlash.h b/libraries/DataFlash/DataFlash.h
index 1a4f13abb5..efd6eebf10 100644
--- a/libraries/DataFlash/DataFlash.h
+++ b/libraries/DataFlash/DataFlash.h
@@ -29,6 +29,8 @@ public:
     // high level interface
     virtual uint16_t find_last_log(void) = 0;
     virtual void get_log_boundaries(uint16_t log_num, uint16_t & start_page, uint16_t & end_page) = 0;
+    virtual void get_log_info(uint16_t log_num, uint32_t &size, uint32_t &time_utc) = 0;
+    virtual int16_t get_log_data(uint16_t log_num, uint16_t page, uint32_t offset, uint16_t len, uint8_t *data) = 0;
     virtual uint16_t get_num_logs(void) = 0;
     virtual void LogReadProcess(uint16_t log_num,
                                 uint16_t start_page, uint16_t end_page, 
diff --git a/libraries/DataFlash/DataFlash_Block.cpp b/libraries/DataFlash/DataFlash_Block.cpp
index 44b8440301..e79b35c6ab 100644
--- a/libraries/DataFlash/DataFlash_Block.cpp
+++ b/libraries/DataFlash/DataFlash_Block.cpp
@@ -88,6 +88,9 @@ void DataFlash_Block::StartRead(uint16_t PageAdr)
     df_Read_BufferNum = 0;
     df_Read_PageAdr   = PageAdr;
 
+    // disable writing while reading
+    log_write_started = false;
+
     WaitReady();
 
     // copy flash page to buffer
@@ -181,3 +184,24 @@ bool DataFlash_Block::NeedErase(void)
     StartRead(1);
     return version != DF_LOGGING_FORMAT;
 }
+
+/*
+  find the number of pages in a log
+ */
+int16_t DataFlash_Block::get_log_data(uint16_t log_num, uint16_t page, uint32_t offset, uint16_t len, uint8_t *data)
+{
+    uint16_t data_page_size = df_PageSize - sizeof(struct PageHeader);
+    if (offset >= data_page_size) {
+        page += offset / data_page_size;
+        offset = offset % data_page_size;
+        page = page % df_NumPages;
+    }
+    if (log_write_started || df_Read_PageAdr != page) {
+        StartRead(page);
+    }
+
+    df_Read_BufferIdx = offset + sizeof(struct PageHeader);
+    ReadBlock(data, len);
+    return (int16_t)len;
+}
+
diff --git a/libraries/DataFlash/DataFlash_Block.h b/libraries/DataFlash/DataFlash_Block.h
index f4ebc5c84f..83f37c3dcd 100644
--- a/libraries/DataFlash/DataFlash_Block.h
+++ b/libraries/DataFlash/DataFlash_Block.h
@@ -26,6 +26,8 @@ public:
     // high level interface
     uint16_t find_last_log(void);
     void get_log_boundaries(uint16_t log_num, uint16_t & start_page, uint16_t & end_page);
+    void get_log_info(uint16_t log_num, uint32_t &size, uint32_t &time_utc);
+    int16_t get_log_data(uint16_t log_num, uint16_t page, uint32_t offset, uint16_t len, uint8_t *data);
     uint16_t get_num_logs(void);
     uint16_t start_new_log(void);
     void LogReadProcess(uint16_t log_num,
diff --git a/libraries/DataFlash/DataFlash_File.cpp b/libraries/DataFlash/DataFlash_File.cpp
index 0a1b4cb387..63d793a74d 100644
--- a/libraries/DataFlash/DataFlash_File.cpp
+++ b/libraries/DataFlash/DataFlash_File.cpp
@@ -227,6 +227,21 @@ uint32_t DataFlash_File::_get_log_size(uint16_t log_num)
     return st.st_size;
 }
 
+uint32_t DataFlash_File::_get_log_time(uint16_t log_num)
+{
+    char *fname = _log_file_name(log_num);
+    if (fname == NULL) {
+        return 0;
+    }
+    struct stat st;
+    if (::stat(fname, &st) != 0) {
+        free(fname);
+        return 0;
+    }
+    free(fname);
+    return st.st_mtime;
+}
+
 /*
   find the number of pages in a log
  */
@@ -236,6 +251,51 @@ void DataFlash_File::get_log_boundaries(uint16_t log_num, uint16_t & start_page,
     end_page = _get_log_size(log_num) / DATAFLASH_PAGE_SIZE;
 }
 
+/*
+  find the number of pages in a log
+ */
+int16_t DataFlash_File::get_log_data(uint16_t log_num, uint16_t page, uint32_t offset, uint16_t len, uint8_t *data)
+{
+    if (!_initialised) {
+        return -1;
+    }
+    if (_read_fd != -1 && log_num != _read_fd_log_num) {
+        ::close(_read_fd);
+        _read_fd = -1;
+    }
+    if (_read_fd == -1) {
+        char *fname = _log_file_name(log_num);
+        if (fname == NULL) {
+            return -1;
+        }
+        _read_fd = open(fname, O_RDONLY);
+        free(fname);
+        if (_read_fd == -1) {
+            return -1;            
+        }
+        _read_offset = 0;
+        _read_fd_log_num = log_num;
+    }
+    uint32_t ofs = page * (uint32_t)DATAFLASH_PAGE_SIZE + offset;
+    if (ofs != _read_offset) {
+        ::lseek(_read_fd, ofs, SEEK_SET);
+    }
+    int16_t ret = (int16_t)::read(_read_fd, data, len);
+    if (ret > 0) {
+        _read_offset += ret;
+    }
+    return ret;
+}
+
+/*
+  find size and date of a log
+ */
+void DataFlash_File::get_log_info(uint16_t log_num, uint32_t &size, uint32_t &time_utc)
+{
+    size = _get_log_size(log_num);
+    time_utc = _get_log_time(log_num);
+}
+
 
 
 /*
@@ -264,6 +324,10 @@ uint16_t DataFlash_File::start_new_log(void)
         _write_fd = -1;
         ::close(fd);
     }
+    if (_read_fd != -1) {
+        ::close(_read_fd);
+        _read_fd = -1;
+    }
 
     uint16_t log_num = find_last_log();
     // re-use empty logs if possible
@@ -307,6 +371,7 @@ void DataFlash_File::LogReadProcess(uint16_t log_num,
     }
     if (_read_fd != -1) {
         ::close(_read_fd);
+        _read_fd = -1;
     }
     char *fname = _log_file_name(log_num);
     if (fname == NULL) {
@@ -317,6 +382,7 @@ void DataFlash_File::LogReadProcess(uint16_t log_num,
     if (_read_fd == -1) {
         return;
     }
+    _read_fd_log_num = log_num;
     _read_offset = 0;
     if (start_page != 0) {
         ::lseek(_read_fd, start_page * DATAFLASH_PAGE_SIZE, SEEK_SET);
diff --git a/libraries/DataFlash/DataFlash_File.h b/libraries/DataFlash/DataFlash_File.h
index a7caf45d55..652a1abaf5 100644
--- a/libraries/DataFlash/DataFlash_File.h
+++ b/libraries/DataFlash/DataFlash_File.h
@@ -30,6 +30,8 @@ public:
     // high level interface
     uint16_t find_last_log(void);
     void get_log_boundaries(uint16_t log_num, uint16_t & start_page, uint16_t & end_page);
+    void get_log_info(uint16_t log_num, uint32_t &size, uint32_t &time_utc);
+    int16_t get_log_data(uint16_t log_num, uint16_t page, uint32_t offset, uint16_t len, uint8_t *data);
     uint16_t get_num_logs(void);
     uint16_t start_new_log(void);
     void LogReadProcess(uint16_t log_num,
@@ -45,6 +47,7 @@ public:
 private:
     int _write_fd;
     int _read_fd;
+    uint16_t _read_fd_log_num;
     uint32_t _read_offset;
     volatile bool _initialised;
     const char *_log_directory;
@@ -65,6 +68,7 @@ private:
     char *_log_file_name(uint16_t log_num);
     char *_lastlog_file_name(void);
     uint32_t _get_log_size(uint16_t log_num);
+    uint32_t _get_log_time(uint16_t log_num);
 
     void _io_timer(void);
 };
diff --git a/libraries/DataFlash/LogFile.cpp b/libraries/DataFlash/LogFile.cpp
index ceb7904b40..12339be4b5 100644
--- a/libraries/DataFlash/LogFile.cpp
+++ b/libraries/DataFlash/LogFile.cpp
@@ -136,6 +136,19 @@ void DataFlash_Block::get_log_boundaries(uint16_t log_num, uint16_t & start_page
     }
 }
 
+// find log size and time
+void DataFlash_Block::get_log_info(uint16_t log_num, uint32_t &size, uint32_t &time_utc)
+{
+    uint16_t start, end;
+    get_log_boundaries(log_num, start, end);
+    if (end >= start) {
+        size = (end + 1 - start) * (uint32_t)df_PageSize;
+    } else {
+        size = (df_NumPages + end - start) * (uint32_t)df_PageSize;
+    }
+    time_utc = 0;
+}
+
 bool DataFlash_Block::check_wrapped(void)
 {
     StartRead(df_NumPages);