unsigned char CSccb::Read(unsigned char addr)
{
unsigned char i, val;
// 2 phase
Start();
Write(m_dev);
Write(addr);
Stop();
Start();
Write(m_dev + 1);
TriState();
for (i=0, val=0; i<8; i++)
{
val <<= 1;
PortWrite(1, 0);
if (DATA_REG&DATA_MASK)
val |= 1;
PortWrite(0, 0);
}
// send NA bit
PortWrite(0, 1);
Drive();
PortWrite(1, 1);
PortWrite(0, 1);
Stop();
return val;
}
void CSccb::Write(unsigned char val)
{
unsigned char i;
for (i=0; i<8; i++, val<<=1)
{
if (val&0x80) // send msb first
{
PortWrite(0, 1);
PortWrite(1, 1);
PortWrite(0, 1);
}
else
{
PortWrite(0, 0);
PortWrite(1, 0);
PortWrite(0, 0);
}
}
// send "don't care" bit
TriState();
PortWrite(0, 0);
PortWrite(1, 0);
PortWrite(0, 0);
Drive();
}
/**
* @brief
* This method transmits au8Buffer to Serial line.
* Only if u8txenpin != 0, there is a flow handling in order to keep
* the RS485 transceiver in output state as long as the message is being sent.
* This is done with UCSRxA register.
* The CRC is appended to the buffer before starting to send it.
*
* @param nothing
* @return nothing
* @ingroup buffer
*/
void ModbusSendTxBuffer()
{
// uint8_t i = 0;
// append CRC to message
uint16_t u16crc = ModbusCalcCRC(_u8BufferSize);
_au8Buffer[ _u8BufferSize ] = u16crc >> 8;
_u8BufferSize++;
_au8Buffer[ _u8BufferSize ] = u16crc & 0x00ff;
_u8BufferSize++;
// transfer buffer to serial line
PortWrite(_au8Buffer, _u8BufferSize);
// keep RS485 transceiver in transmit mode as long as sending
//!!! port->flush();
_u8BufferSize = 0;
// set time-out for master
_u32timeOut = millis() + (unsigned long) _u16timeOut;
// increase message counter
_u16OutCnt++;
}
CSccb::CSccb(unsigned char dev)
{
m_dev = dev;
DIR_REG |= CLK_MASK;
TriState(); // set clock as output, data tristate
PortWrite(1, 0); // set clock high (idle)
//
#if 0
volatile unsigned long val;
Drive();
PortWrite(0, 0);
PortWrite(0, 1);
PortWrite(1, 0);
PortWrite(1, 1);
TriState(); // set clock as output, data tristate
val = DATA_REG&DATA_MASK;
val = DATA_REG&DATA_MASK;
val = DATA_REG&DATA_MASK;
#endif
}
void MemMapper::Reset()
{
PortWrite(0, 0);
}
