Samsung Ht As700 User Manual

							111
Structure of Communication Frames
The function code is explained with the example of Query and 
Response frame based on the 2-step communication.
Query (Q) and Response (R) frame
Query Acknowledge (QA) frame
Response Request (RR) frame
Response (R) frame for an errorDA SA Function code Length Information CRC L CRC H
Length of information area 
(byte)
1 to 255: 1 to 255 bytes
0: 256 bytes
Function code
Sender ID
Receiver ID
DA SA $80 01 00 CRC L CRC H
DA SA $00 01 00 CRC L CRC H
DA SA $8X 01 Error No CRC L CRC H
CRC-16 code
(2 bytes)
Constant
Error #1. Wrong communication function code
Error #2. Out of range
Error #3. Wrong frame structure
Error #4. CPU did not perform
Error #5. Frame is too long 
The frame is sent from SA 
to DA. After Q or RR is sent, 
DA and SA for the QA and 
R from the CPU are 
replaced each other, 
because the CPU becomes 
the sender and the 
peripheral device becomes 
the receiver of the 
message. 
Constant
 
						

							112
Read the content of the bits (R, L, M, K, F, or TC) assigned to the absolute address.
Can read n consecutive bits (On/Off).
Query (Q) frame
Response (R) frameDA SA $21 $03BAS
L      HNCRC
L      H
DA SA $A1 NBase + 0
bit valueBase + 1
bit value-Base + N-1
bit valueCRC
L     H
Length of information (byte) 
Peripheral device ID (PC ID)
Bits that are On are represented by the one byte value $FF. 
Bits that are Off have a value of $00.
Absolute bit address (address of 
first bit to read)
Refer to 3.3 Absolute Addressing
Ex) K127.12 (address K127’s 12
th bit)
Absolute bit address = $1BFC
BASE L=$FC, H=$1B
Number of bits to be read 
Length of information (number of bytes): from the length to the next CRC.
Response code where $80 is added to the R (Response) Q to its 2-step 
communication function code
PLD ID (CPU ID)
Peripheral device ID (PC ID)
For the response, the PLC is the sender and 
the PLC the receiver, so the DA and SA are 
reversed from the Q message.
PLD ID (PC ID)
Read bits
Function code 
(2-step communication)
 
						

							113
Modify the contents of the bits stored in the absolute address (R, L, M, K, F, or TC).
Change the bit state between On/Off.
Can change multiple consecutive bytes. 
Query (Q) frame
Response (R) frame
Read the content of the words (R, L, M, K, F, or W) assigned to the absolute address.
Can read n consecutive words. 
Query (Q) frame
Response (R) frameDA SA $22 N
Base
L       HBase+0
bit valueBase+N+1
bit value-Base+N-3bit 
valueCRC
L       H
DA SA $A2 &01
&00CRC
L       H
DA SA $23 $30Base
L       HNCRC
L       H
DA SA $A3 LBase+0word
L       HBase+1word
L       H-Base+1word
L       HCRC
L       H
Completion code
Fixed
N word values from the base words requested by the Q.
Length L = Nx2
To turn On the desired bit value from the base, enter $FF. 
To change to Off, enter $00.
Absolute bit address (starting address)
Refer to Absolute Addressing on Chapter 3.
Word absolute address (starting address)
Refer to Absolute Addressing on Chapter 3.
Ex) Absolute address of K127 word is $01BF.
BASE L=$BF, H=$01
Number of words to be read
Write bits
Read words
 
						

							114
Change the content of the words (R, L, M, K, F, or W) assigned to the absolute address.
Can read n consecutive words. 
Query (Q) frame
Response (R) frame
Read the bits and/or word contents of the assigned absolute addresses.
Can read bits and words regardless of their order and location in memory. 
Query (Q) frame
Response (R) frameDA SA $24 L
Base
L       HBase+0word
L       H-Base+1word
L       HCRC
L       H
DA SA $A2 $01
&00CRC
L       H
DA SA $25 LAO
L       HA1
L       H-An
L       HCRC
L       H
DA SA $A5 LxDO D1
L       H-Dn
L       HCRC
L       H
n word values from the base words requested by the Q.
Length L = Nx2+2
Assigning absolute address for bits
Absolute address for the K127 12th bit =$1BFC 
A x = 0 0 01 1011  1111  1010  
Ax L=$FC, H=$1B
Assigning addresses for word
Absolute address for the K127 word =$01BF 
A x = 010 0  0 0 01  1011  1111  
Ax L=$BF, H=$41
For the A0, A1, ..., An requested by the Q, the 
content D0, D1, ..., Dn of the word/bit is returned. 
If Ax denotes a bit address, the Dx data is 1 byte 
(On = $FF, Off = $00), and if Ax denotes a word 
address, the Dx data is 1 word (2 bytes).
The size and location of the returned data 
depends on the combination of bit/word 
addresses requested. The Lx parameter 
should be checked to verify data size. 
Fixed
Method of assigning bit/word
absolute address
   
15  14  13                                    0
   0      0   Absolute bit address
   0      1   Absolute word address
   1      X   Not used
    
Ax=A0, A1, .., An Dx=D0, D1, .., Dn
Absolute Address(Bit/Word)
Write words
Read bits and words
 
						

							115
Read the bits and/or word contents of the assigned absolute addresses.
Can read bits and words regardless of their order and location in memory.
Query (Q) frame
If Ax denotes a bit address, the Dx data is 1 byte (On=$FF, Off=$00), and 
if Ax denotes a word address, the Dx is 1 word (2 bytes). 
Response (R) frameDA SA $26 L
AO
L       HDOA1
L       H-CRC
L       H
DA SA $A2 $01
$00CRC
L       H
Method of assigning bit/word
absolute address
   
15  14  13                                     0
   0      0   Absoulte bit address
   0      1   Absoulte word address
   1      X   Not used
  Ax=A0, A1, .., An Dx=D0, D1, .., Dn
                      
Absolute Address(Bit/Word)
Assigning absolute addresses for bits
Absolute address for the K127.12 bit = 
$1BFC
A x = 0 0 01 1011  1111  1010
Assigning absolute addresses for word
The absolute address for the K127 word = 
$01BF
A X = 010 0 0 0 01 1011  1111
When structuring the outgoing frame, be aware that the Dx of the 
Q changes according to the bit/word Ax type, and the L (information length) 
changes as well. The Dx will be either 1 or 2 bytes.
Fixed
Write bits and words
 
						

							116
Communication Program Examples
Users can write a communication program by using the following 
example. For more information, contact the sales or technical 
department.
ProgramNotes

#include 
#include 
#include 
#define PC_ID 0xE2
#define time_limit 28
#define retrial_limit 2
#define TRUE 1
#define FALSE 0
#define lower_byte(x) (unsigned int) ((x)& 0x00FF)
#define upper_byte (x) (unsigned int) (((x)& 0xFF00)>>8)
typedef int BOOL;
unsigned int PORTADD,DIVISOR,sending_delay, receiving_delay;
unsigned int sending_frame[262],receiving_frame[262];
unsigned int Crc;
unsigned int card,i,ix,iy,smode;
unsigned int port_number;
unsigned int PlcID,OldID;
BOOL Success;
unsigned int data,JobID,retrialC;
unsigned int Old,New,receiving_Index_max,sending_Index_max,
index,watchdog;
unsigned int M[128],K[128]; /* Example Register */
void RR_occurring(void);
void Trsport(unsigned int);
unsigned int Recport(void);
BOOL sending_occuring(void);
BOOL receiving_occuring (void);
void Crc16(unsigned int);
void Job(void);
unsigned int communication(void);
void Mword_reading(void);
void Kword_writing(void);
void main(void)
{
unsigned int i;
/* Selection of communication port */
clrscr();
printf(PORT : COM1[1]/ COM[2]/ GPC-232[3]/GPC-485[4]/GPC-
Parallel[5] = );
scanf(%d,&port_number);
if ((port_number < 1) || (port_number > 5)) port_number=5;
/* Selection of Baudrate for Serial communication */
sending_delay=10;
if (port_number != 5)
{
printf(GPC card BAUD-RATE : 9600[1]/ 4800[2]/ 2400[3] = );
scanf(%d,&i);
if ((i < 1) || (i > 3)) i=1;
if (i == 3) i=4;
if ((port_number == 1) || (port number == 2)) DIVISOR=12 * i;
else DIVISOR=40 * i;
receiving_delay=3 * i + 1;
}This program was written in Borland C++. It uses the peripheral devices 
such as PC to read M000 to M127 words, stores them in the K000 to K127, 
and then compares the two registry values and indicates the results on the 
screen using the OK or the FAIL notation. The user may read or 
manipulate the various communication function codes and the sent/
received information to control the PLC in various ways.
This program consists of a header, the main program, and various 
functions. The buffers and variables needed to store the communication 
data are set as global variables, so that the main and various other 
functions may reference them.  
By using the COM1 and COM2 ports of the computer, serial 
communication is possible. By using the GPU-300 card, parallel 
communication is also enabled. 
The Qs, QAs, RRs, and Rs are handled in the job function. If there is any 
communication delay or frame breakdown, retry 3 times, then issue a 
communication error.
The procedure of the communication, according to the JobID is:
1.Q sending
2.QA receiving 
3.RR sending
4.R receiving
When an error occurs in a frame, a retransmission should be made.

1. Adjusts the initial communication port and the board rate for 
communication. Then initializes the variables. 
2. Using the communication function codes, reads the data of the M field, 
reads the word values of the M0 to M127 word area. The K registers are 
the retentive registers.  
3. Uses the communication code to read the data of the K area. 
4. Compares the values of the M area and the values of the K area, and 
indicates OK when the values are the same. 
Beginning of the main program
Select the port of the peripheral device for the communication
:Serial 9 pins, 25 pins
Parallel GPU-300 parallel port
Select board rate: 
9600 bps (max):
4800 bps
2400 bps
Set the communication environment (delay time) for the selected ports.
Note: GPC-300 card port address = 0x0300
 
						

							117
ProgramNotes
* Initialization of GPC card */
if(port_number == 1) PORTADD=0x3F0;
if(port_number == 2) PORTADD=0x2F0;
if ((port_number >= 3) && (port_number 1)^0xA001; /* 0x0001 :  
    multi-nominal expression */
    else Crc=Crc>>1;
    }
    }GPC-300 card Setting (8255chip setting) 
Uses the communication card that is connected, and sets the environment 
according to the PLC communication specifications, so that 
communication is possible.
 
CPU-ID: Input PLC ID (0 to 255) 
Reads the register value for the M area (M0 to M127)
Stores the value for the M area in the K area. (K0 to K127)
RR (Request Response) request function 
Sends data to the communication port.
Reads the received data from the communication port.
Outputs the data when a Send event occurs..
Inputs the data when a Receiver event occurs.
CRC calculation
Encodes the communication data in the byte stream. Any completed 
communication function will be attached to the latest frame or will be 
compared with the attached CRC to check for data errors. 
(Note: The CRC method can be implemented in several ways within the 
rule specified as shown in the left code.) 
 
						

							118
ProgramNotes
void Job(void)
    {
    /* JobID=0  : Change to sending-mode for serial port */
    /* JobID=1  : Transmit sending-frame                 */
    /* JobID=2  : Change to receiving-mode for serial port */
    /* JobID=3  : Address polling of ACK from CPU   */
    /* JobID=4  : Receive ACK from CPU              */
    /* JobID=5  : Change to sending-mode for serial port */
    /* JobID=6  : Transmit RR-Frame                 */
    /* JobID=7  : Change to receiving-mode for serial port */
    /* JobID=8  : Address polling of RES from CPU   */
    /* JobID=9  : Receive RES from CPU              */
    /* JobID=10 : Success communication processing  */
    switch(JobID)
    {
    case 0: case 5:if (port_number != 5)
    {
    if (port_number == 4) outportb(0x301,0xFF);
    else outportb(PORTADD+0x0C,(inportb(PORTADD+0x0C) | 
    0x02));
    delay(sending_delay);
    }
    if (JobID == 5) RR_occuring();
    watchdog=0; index=0; sending_Index_max=5; Crc=0xFFFF;        
    JobID++;
    break;
    case 1: case 6:if (receiving_occuring()) data=Recport();
    if (sending_occuring())
    {
    if (index
						

							119
ProgramNotes
   break;
   case 4:
   case 9:if(receiving_occuring())
   {
   if(indexTime_limit)
    {
    watchdog=0; retrialC--;
    JobID=(JobID & 0x05);
    }
    if(!(((Old^New) & 0x02)==0))
    {
    watchdog=watchdog+1;
    Old=New;
    }
    }while((retrialC!=0) && (Success==FALSE));
    if(retrialC==0) ret=1;
    else ret=0;
    return(ret);
    }
void Mword_reading(void)
    {
    /* Example of Read-Register */
    int  i;
    receiving_frame[2]=3;/* EXAMPLE READ WORD(M000-M0127) */
    receiving_frame[3]=3;/* Number Of Byte For Information = 3 */
    receiving_frame[4]=0xC0;/* BASE(M000=$00c0) */
    receiving_frame[5]=0;/* BASE HIGH  */
    receiving_frame[6]=128;/* Number Of Byte M000-M127 */
    if(communication() == 0)
    {
    printf(READ M0000-M0127 OK
);
   for(i=0;i
						

							120
ProgramNotes
 if(communication() == 0) printf(WRITE K0000-K0063 OK\n);
    else printf(communication error\n);
    receiving_frame[2]=4;            /* EXAMPLE write WORD(K064-K0127) */
    receiving_frame[3]=130;        /* Number Of Byte For Information */
    receiving_frame[4]=0x80;      /* BASE(K000=$0180) LOW */
    receiving_frame[5]=1;             /* BASE HIGH  */
    for(i=0;i