Symbol Type Value

Type value

Characters contain

Example

Notes

[0 → 9]

0123456789

0 , 123, 457

Number only

[a → z]

abcdefghijklmnopqrstuvwxyz

esprtk

 

[A → Z]

ABCDEFGHIJKLMNOPQRSTUVWXYZ

ESPRTK

 

[INTEGER]

-0123456789

0 , -123, -457

Number only and ‘-’

[FLOAT]

-0123456789.

0.123 , -12.23 , 67.97

Number only and ‘-’ and ‘.’

[BIT]

01

011101, 1111001, 001

‘0’ and ‘1’ only

[HEX_Up]

0123456789ABCDEF

A0,B0, C045, AD7C,

A8E4C0D2

1 byte of data must be represented by 2 characters.

[HEX]

0123456789acbdefABCDEF

A0,b7, a3ee, B3f5,

A8E4c0d2

1 byte of data must be represented by 2 characters.

[<CR><LF>]

2 byte value are 0x0D , 0x0A

 

 

[PRINT]

abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLM

NOPQRSTUVWXYZ0123456789 "#%&'()+,-./:;<=>@^_`{}~

Hello_ESPrtk_01 ,

Hello-ESPrtk-02 ,

Hello ESPrtk $# ,

Not allow contain <CR><LF>, $*|

[STRING]

AbcdefghijklmnopqrstuvwxyzABCDEFGHIJKLM

NOPQRSTUVWXYZ0123456789 -_+(.):,

Hello_ESPrtk_01 ,

Hello-ESPrtk-02 ,

Not allow contain <CR><LF>, WhiteSpace , !=&"~<\/>?|%#[]{}^$*

[PASS_A]

[STRING]

 

Not allow contain <CR><LF>, , !=&"~<\/>?|%#[]{}^$*

[PASS_B]

[PASS_A]

 

Not allow contain WhiteSpace

[PASS_C]

[PASS_A]

 

Must contain atleast

1 Upper Case and

1 Lower Case and

1 Number

Min length 8 chars

[PASS_D]

[PASS_C]

 

Not allow contain WhiteSpace


 

Format the message frame communicating on the port UART0.

Message Frame:

<Header> + <Length_Payload> + <Payload> + <*CRC> + <CR> <LF>

 

Example : $ESPLOG|25|2|INFO|GO to MAIN ACTION|*6360

 

Label

Characters allowed to contain.

<Header>

[0 → 9] [a → z] [A → Z]

<Length_Payload>

[0 → 9]

<Payload>

[ASC]

<*CRC>

[HEX_Up]

<CR><LF>

[<CR><LF>]

 

Label

Sub

Min Bytes

Max Bytes

Describe

<Header>

‘$’ + ‘Header_Name’ + ‘|’

3

10

Start Message

<Length_Payload>

Length_Payload’ +’|’

2

10

Numbers Bytes of Payload

<Payload>

‘Payload’

1

Length_Payload

Payload data

<*CRC>

‘*’ + ‘CRC_16’

5

5

Checksum of Message

<CR><LF>

0x0D + 0x0A

2

2

End Message

 

 

<Header>

<Length_Payload>

<Payload>

<*CRC>

<CR><LF>

Ex 1

$ESPLOG|

25|

2|INFO|GO to MAIN ACTION|

*6360

\r\n

Ex 2

$ESPLOG|

34|

1|ERROR|0,0,G-G-G-G,<br> No ERROR|

*7A58

\r\n

Ex 3

$ESP_OK|

5|

X|_||

*5309

\r\n

Ex 4

$ESP_OK|

14|

W|m|3|0|0|0|0|

*6D76

\r\n

Length_Payload calculate.

  • Example message : $ESP_OK|14|W|m|3|0|0|0|0|*6D76

  • Then Payload range is : W|m|3|0|0|0|0| and Total of characters (Length) is 14

CRC calculate.

CRC_Range calculate from after '$' to begin '*' ( not contain '$' and '*')

Header_Name’ + ‘|’+ <Length_Payload> + <Payload>

 

  • Example message : $ESP_OK|14|W|m|3|0|0|0|0|*6D76

  • Then CRC Range is: ESP_OK|14|W|m|3|0|0|0|0|

CRC16 Algorithm calculate in C/C++ for ESPrtk frame:

	#include <stdio.h>
const char  MSG[]= "$ESP_OK|14|W|m|3|0|0|0|0|*????\r\n";
  
  // Calculate CRC
  uint8_t FIRST_CRC  = 0 ;
  uint8_t SECOND_CRC = 0 ;
  uint16_t  i = 0 ;

  while ( MSG [i]  !=  '*' ){ 
    // CRC_Range calculate from after '$' to begin '*'  ( not contain '$' and '*') 
    if (  MSG [i]  != '$' ){ 
       FIRST_CRC     ^=  ( uint8_t  ) MSG [i];
       SECOND_CRC ^=  ( uint8_t ) FIRST_CRC; 
    }
    i++;
  }

  //Format CRC to [HEX_Up] string and store to buffer
  char CRC16_OUT  [4+1] ; 
  sprintf (  CRC16_OUT   ,  "%02X%02X" , FIRST_CRC , SECOND_CRC );

  //Print out result            
  printf ( "\n Your CRC16 is %s \n", CRC16_OUT);
  //Result should be [ Your CRC16 is 6D76 ]

ESPrtk support suggestions for fixing errors.


When ESPrtk receives an incorrectly structured message frame, it returns a NACK message.

If the message is valid and corrupted, ESPrtk will give an error and suggest correction.

A valid structured message (minimum) must include <Header> <Length_Payload> <Payload> <* CRC>, for example: $ESP_OK|??|?|?|*????


Note : The error correction suggestion function is only fully supported when running in UART Configure mode.

Examples:


HOST Send

$ESP_OK|??|?|?|*????

Respond

NACK :[?] LENGTH_MESSAGE invalid (not a number) - [?] Do you mean LENGTH_MESSAGE = 4


HOST Send

$ESP_OK|4|?|?|*????

Respond

NACK : Your_CRC = [????]: [?] Do you mean Checksum_CRC = 295A


HOST Send

$ESP_OK|?|P|_||*????

Respond

NACK :[?] LENGTH_MESSAGE invalid (not a number) - [?] Do you mean LENGTH_MESSAGE = 5


HOST Send

$ESP_OK|5|P|_||*????

Respond

NACK : Your_CRC = [????]: [?] Do you mean Checksum_CRC = 5B01


HOST Send

$ESP_OK|5|P|_||*5B01

Respond

$ESP_OK|5|P|_||*5B01