SNICInterface for ThingPlug Example

Dependents:   ThingPlug_WiFi_Example ThingPlug_WiFi_Example_2

Fork of SNICInterface by muRata

SNIC/SNIC_UartMsgUtil.cpp

Committer:
kishino
Date:
2014-03-25
Revision:
12:0254eaccfda2
Child:
14:54378c96d285

File content as of revision 12:0254eaccfda2:

#include "SNIC_UartMsgUtil.h"

using namespace murata_wifi;

C_SNIC_UartMsgUtil::C_SNIC_UartMsgUtil()
{
}

unsigned short C_SNIC_UartMsgUtil::makePayload( unsigned int cmd_len, unsigned char *cmd_p, unsigned char *payload_p )
{
    unsigned short payload_len = 0;
    int i;
    
    for( i = 0; i < cmd_len; i++, payload_p++, payload_len++ )
    {
        /* check Escape code */
        if( ( cmd_p[i] == UART_CMD_SOM ) || ( cmd_p[i] == UART_CMD_EOM ) || ( cmd_p[i] == UART_CMD_ESC ) )
        {
            /* Add ESC */
            *payload_p = UART_CMD_ESC;
            payload_len++;
            
            payload_p++;
            *payload_p = (0x80 | cmd_p[i]);
        }
        else
        {
            *payload_p = cmd_p[i];
        }
    }
    
    return payload_len;
}

unsigned int C_SNIC_UartMsgUtil::makeRequest( unsigned char cmd_id,unsigned char *payload_p
                                , unsigned short payload_len, unsigned char *uart_command_p )
{
    unsigned char check_sum = 0;    // Check Sum
    unsigned int  uart_cmd_len = 0;
    int i;
    
    // set SOM
    *uart_command_p = UART_CMD_SOM;
    uart_command_p++;
    uart_cmd_len++;
    
    // set payload length L0
    *uart_command_p = (0x80 | (payload_len & 0x007f));
    check_sum += *uart_command_p;
    uart_command_p++;
    uart_cmd_len++;

    // set payload length L1
    *uart_command_p = (0x80 | ( (payload_len >> 7) & 0x003f));
    check_sum += *uart_command_p;
    uart_command_p++;
    uart_cmd_len++;
    
    // set Command ID
    *uart_command_p = (0x80 | cmd_id);
    check_sum += *uart_command_p;
    uart_command_p++;
    uart_cmd_len++;

    // set Payload
    for( i = 0; i < payload_len; i++, uart_command_p++, uart_cmd_len++ )
    {
        *uart_command_p = payload_p[i];
        check_sum += *uart_command_p;
    }

    // set Check sum
    *uart_command_p = (0x80 | check_sum);
    uart_command_p++;
    uart_cmd_len++;
    
    // set EOM
    *uart_command_p = UART_CMD_EOM;
    uart_cmd_len++;
    
    return uart_cmd_len;
}

unsigned int C_SNIC_UartMsgUtil::getResponsePayload( unsigned int recvdata_len, unsigned char *recvdata_p
                                            , unsigned char *command_id_p,  unsigned char *payload_p )
{
    unsigned short payload_len  = 0;
    unsigned int   response_len = 0;
    unsigned char *buf = NULL;
    bool isESC = false;
    int i;
    
    // get payload length
    payload_len = ( ( (recvdata_p[1] & ~0x80) & 0xff) | ( ( (recvdata_p[2] & ~0xC0) << 7) & 0xff80) );

    // get Command ID
    *command_id_p = (recvdata_p[3] & ~0x80);

    buf = &recvdata_p[4];

    // get payload data
    for( i = 0; i < payload_len; i++, buf++ )
    {
        if( isESC )
        {
            *payload_p = (*buf & ~0x80);
            payload_p++;
            response_len++;
            isESC = false;
        }
        else
        {
            // Check Escape code
            if( *buf == UART_CMD_ESC )
            {
                isESC = true;
                continue;
            }
            else
            {
                *payload_p = *buf;
                payload_p++;
                response_len++;
            }
        }
    }

    return response_len;
}