Modbus Function Codes for Holding/Input Registers
Modbus Function Codes for Holding/Input Registers
Functions
void Modbus::get_FC1 ()
void Modbus::get_FC3 ()
int8_t Modbus::process_FC16 (uint16_t *regs, uint8_t u8size)
This method processes function 16 This method writes a word array assigned by the master.
int8_t Modbus::process_FC3 (uint16_t *regs, uint8_t u8size)
This method processes functions 3 & 4 This method reads a word array and transfers it to the master.
int8_t Modbus::process_FC6 (uint16_t *regs, uint8_t u8size)
This method processes function 6 This method writes a value assigned by the master to a single word.
Function Documentation
get_FC1()
get_FC1Modbus Function Codes for Holding/Input Registers
Modbus Function Codes for Holding/Input Registersget_FC1
void Modbus::get_FC1 ( )[private]
This method processes functions 1 & 2 (for master) This method puts the slave answer into master data buffer
TODO: finish its implementation
Definition at line 1261 of file ModbusRtu.h.
01262 {
01263 uint8_t u8byte, i;
01264 u8byte = 0;
01265
01266 // for (i=0; i< au8Buffer[ 2 ] /2; i++) {
01267 // au16regs[ i ] = word(
01268 // au8Buffer[ u8byte ],
01269 // au8Buffer[ u8byte +1 ]);
01270 // u8byte += 2;
01271 // }
01272 }
get_FC3()
get_FC3Modbus Function Codes for Holding/Input Registers
Modbus Function Codes for Holding/Input Registersget_FC3
void Modbus::get_FC3 ( )[private]
This method processes functions 3 & 4 (for master) This method puts the slave answer into master data buffer
Definition at line 1280 of file ModbusRtu.h.
01281 {
01282 uint8_t u8byte, i;
01283 u8byte = 3;
01284
01285 for (i = 0; i < au8Buffer[2] / 2; i++)
01286 {
01287 au16regs[i] = word(
01288 au8Buffer[u8byte],
01289 au8Buffer[u8byte + 1]);
01290 u8byte += 2;
01291 }
01292 }
process_FC16()
process_FC16Modbus Function Codes for Holding/Input Registers
Modbus Function Codes for Holding/Input Registersprocess_FC16
int8_t Modbus::process_FC16 (uint16_t * regs, uint8_t u8size)[private]
This method processes function 16 This method writes a word array assigned by the master.
Returns
u8BufferSize Response to master length
Definition at line 1502 of file ModbusRtu.h.
01503 {
01504 uint8_t u8func = au8Buffer[FUNC]; // get the original FUNC code
01505 uint8_t u8StartAdd = au8Buffer[ADD_HI] << 8 | au8Buffer[ADD_LO];
01506 uint8_t u8regsno = au8Buffer[NB_HI] << 8 | au8Buffer[NB_LO];
01507 uint8_t u8CopyBufferSize;
01508 uint8_t i;
01509 uint16_t temp;
01510
01511 // build header
01512 au8Buffer[NB_HI] = 0;
01513 au8Buffer[NB_LO] = u8regsno;
01514 u8BufferSize = RESPONSE_SIZE;
01515
01516 // write registers
01517 for (i = 0; i < u8regsno; i++)
01518 {
01519 temp = word(
01520 au8Buffer[(BYTE_CNT + 1) + i * 2],
01521 au8Buffer[(BYTE_CNT + 2) + i * 2]);
01522
01523 regs[u8StartAdd + i] = temp;
01524 }
01525 u8CopyBufferSize = u8BufferSize + 2;
01526 sendTxBuffer();
01527
01528 return u8CopyBufferSize;
01529 }
process_FC3()
process_FC3Modbus Function Codes for Holding/Input Registers
Modbus Function Codes for Holding/Input Registersprocess_FC3
int8_t Modbus::process_FC3 (uint16_t * regs, uint8_t u8size)[private]
This method processes functions 3 & 4 This method reads a word array and transfers it to the master.
Returns
u8BufferSize Response to master length
Definition at line 1357 of file ModbusRtu.h.
01358 {
01359
01360 uint8_t u8StartAdd = word(au8Buffer[ADD_HI], au8Buffer[ADD_LO]);
01361 uint8_t u8regsno = word(au8Buffer[NB_HI], au8Buffer[NB_LO]);
01362 uint8_t u8CopyBufferSize;
01363 uint8_t i;
01364
01365 au8Buffer[2] = u8regsno * 2;
01366 u8BufferSize = 3;
01367
01368 for (i = u8StartAdd; i < u8StartAdd + u8regsno; i++)
01369 {
01370 au8Buffer[u8BufferSize] = highByte(regs[i]);
01371 u8BufferSize++;
01372 au8Buffer[u8BufferSize] = lowByte(regs[i]);
01373 u8BufferSize++;
01374 }
01375 u8CopyBufferSize = u8BufferSize + 2;
01376 sendTxBuffer();
01377
01378 return u8CopyBufferSize;
01379 }
process_FC6()
process_FC6Modbus Function Codes for Holding/Input Registers
Modbus Function Codes for Holding/Input Registersprocess_FC6
int8_t Modbus::process_FC6 (uint16_t * regs, uint8_t u8size)[private]
This method processes function 6 This method writes a value assigned by the master to a single word.
Returns
u8BufferSize Response to master length
Definition at line 1421 of file ModbusRtu.h.
01422 {
01423
01424 uint8_t u8add = word(au8Buffer[ADD_HI], au8Buffer[ADD_LO]);
01425 uint8_t u8CopyBufferSize;
01426 uint16_t u16val = word(au8Buffer[NB_HI], au8Buffer[NB_LO]);
01427
01428 regs[u8add] = u16val;
01429
01430 // keep the same header
01431 u8BufferSize = RESPONSE_SIZE;
01432
01433 u8CopyBufferSize = u8BufferSize + 2;
01434 sendTxBuffer();
01435
01436 return u8CopyBufferSize;
01437 }