Diff: cmd_io.cpp

Revision:

0:d33360d14a57

diff -r 000000000000 -r d33360d14a57 cmd_io.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/cmd_io.cpp	Thu Nov 17 17:03:22 2011 +0000
@@ -0,0 +1,161 @@
+//
+// cmd_io.cpp : library of routines to communicate with virtual COM port
+// ==========
+//
+#include    "mbed.h"
+#include    "cmd_io.h"
+#include    "globals.h"
+
+//************************************************************************
+//
+// get_cmd - read a command string from the serial port
+// =======
+// 
+// Method
+//      1. Read string of data until a Newline character
+//            string is passed as the parameter
+//      2. return a sting through the pointer and a count of the number of characters
+//
+// Notes
+//
+uint32_t get_cmd(CMD_STRUCT *command)
+{
+char   ch;
+uint8_t  i;
+//
+// read string and use newline as terminator
+//
+    for (i= 0  ; i < CMD_STR_BUFFER_SZ ; i++) {
+        ch = pc.getc();
+        if (ch == '\r') {
+            continue;
+        }
+        command->cmd_str[i] = ch;
+        if (ch == '\n') {
+            command->cmd_str[i] = '\0';
+            break;
+        }
+    }
+    command->char_cnt = i;    // record character count
+    command->result_status = OK;
+    return 0;
+}
+
+//************************************************************************
+//
+// parse_cmd - split command into its component parts
+// =========
+// 
+// Method
+//      1. first character is the command code
+//      2. subsequent character define a set of parameters
+//
+//        String is located in the CMD_STRUCT and the resulting
+//        data is returned to the same structure.
+//
+// Notes
+//
+uint32_t parse_cmd(CMD_STRUCT *command)
+{
+uint8_t  param_cnt, i, state;
+uint16_t tmp;
+
+    command->cmd_code = command->cmd_str[0];
+    param_cnt = 0;
+    tmp = 0;
+    state = 0;
+    for (i=1 ; i < CMD_STR_BUFFER_SZ ; i++) {    // step through characters
+        if (command->cmd_str[i] == '\0') {
+            if (state == 1) {     // count paramter that is terminated by NEWLINE
+                command->param[param_cnt] = tmp;
+                param_cnt++;
+            }
+            command->nos_params = param_cnt;
+            return OK;
+        }
+        if ((command->cmd_str[i] == ' ') && (state == 0)) {        // skip spaces
+            continue;        
+        }
+        if ((command->cmd_str[i] == ' ') && (state == 1)) {        // skip spaces
+            state = 0;
+            command->param[param_cnt] = tmp;
+            param_cnt++;
+            tmp = 0;
+            continue;        
+        }
+        state = 1;
+        if ((command->cmd_str[i] >= '0') && (command->cmd_str[i] <= '9')) {
+            tmp = (tmp * 10) + (command->cmd_str[i] - '0');
+        } else {
+            command->param[param_cnt] = tmp;
+            return CMD_BAD_CHARACTER;
+        }
+    }
+    return CMD_NO_TERMINATOR;
+}
+
+//************************************************************************
+//
+// reply_to_cmd - return data and status info
+// ============
+// 
+// Method
+//
+// Notes
+//
+void reply_to_cmd(CMD_STRUCT *command)
+{
+    send_status(command->result_status);
+    if ((command->result_status == OK) && (command->nos_data > 0)) {
+        send_data(command);
+    }
+}
+
+//************************************************************************
+//
+// send_status - command status
+// ===========
+//
+// Notes
+//        return status value as a positive interger in a string format
+//        with a terminating newline character.
+//
+void send_status(uint32_t  value)
+{
+    pc.printf("%d\n", value);
+    return;
+}
+
+//************************************************************************
+//
+// send_data - send data appropriate to the command 
+// =========
+// 
+// Method
+//
+// Notes
+//
+void send_data(CMD_STRUCT *command)
+{
+char buffer[80];
+uint8_t i;
+//
+// create data string
+//
+    if (command->nos_data == 1) {
+        sprintf(buffer, "%u\n", (int)command->result_data[0]);
+    }
+    if (command->nos_data == 2) {
+        sprintf(buffer, "%u %u\n", (int)command->result_data[0], (int)command->result_data[1]);
+    }
+//
+// send string
+//
+    for (i = 0 ; i < 40 ; i++) {
+        if (buffer[i] == '\0') {    // do not send NULL character
+            return;
+        }
+        pc.putc(buffer[i]);
+    }
+    return;
+}
\ No newline at end of file