/************************************************************************** * * Copyright (C) 2005 Steve Karg * * Permission is hereby granted, free of charge, to any person obtaining * a copy of this software and associated documentation files (the * "Software"), to deal in the Software without restriction, including * without limitation the rights to use, copy, modify, merge, publish, * distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * The above copyright notice and this permission notice shall be included * in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. * *********************************************************************/ #if PRINT_ENABLED #define PRINT_ENABLED_RS485 1 #else #define PRINT_ENABLED_RS485 0 #endif #include #include #include #include #if PRINT_ENABLED_RS485 #include #endif #include "mstp.h" /* note: use the RTKernel-C API so that it can use this library */ #define RS485_IO_ENABLE(p) ModemControl(p,0,DTR); #define RS485_TRANSMIT_ENABLE(p) ModemControl(p,1,RTS); #define RS485_RECEIVE_ENABLE(p) ModemControl(p,0,RTS); /* COM port number - COM1 = 0 */ static int RS485_Port = COM2; /* baud rate */ static long RS485_Baud = 9600; /* io base address */ static long RS485_Base = 0; /* hardware IRQ number */ static long RS485_IRQ_Number = 0; #if PRINT_ENABLED_RS485 static FineTime RS485_Debug_Transmit_Timer; #endif #if PRINT_ENABLED_RS485 void RS485_Print_Frame( int port, FineTime timer, uint8_t * buffer, /* frame to send (up to 501 bytes of data) */ uint16_t nbytes) { uint16_t i; /* byte counter */ unsigned long duration; /* measures the time from last output to this one */ unsigned long seconds; unsigned long milliseconds; duration = ElapsedMilliSecs(timer); seconds = duration / 1000U; milliseconds = duration - (seconds * 1000U); fprintf(stderr, "%0lu.%03lu: COM%d:", seconds, milliseconds, port + 1); for (i = 0; i < nbytes; i++) { unsigned value; value = buffer[i]; fprintf(stderr, " %02X", value); } fprintf(stderr, "\n"); fflush(stderr); } #endif static void RS485_Standard_Port_Settings( long port, long *pIRQ, long *pBase) { switch (port) { case COM1: *pBase = (long) 0x3F8; *pIRQ = 4L; break; case COM2: *pBase = (long) 0x2F8; *pIRQ = 3L; break; case COM3: *pBase = (long) 0x3E8; *pIRQ = 4L; break; case COM4: *pBase = (long) 0x2E8; *pIRQ = 3L; break; default: break; } } static int TestCOMPort( int Base) { /* base address of UART */ int i; for (i = 0; i < 256; i++) { RTOut(Base + 7, (BYTE) i); /* write scratch register */ RTOut(Base + 1, RTIn(Base + 1)); /* read/write IER */ if (RTIn(Base + 7) != i) /* check scratch register */ return FALSE; } return TRUE; } static RS485_Open_Port( int port, /* COM port number - COM1 = 0 */ long baud, /* baud rate */ unsigned base, /* io base address */ int irq) { /* hardware IRQ number */ if (!TestCOMPort(base)) return; /* setup the COM IO */ SetIOBase(port, base); SetIRQ(port, irq); if (irq < 8) RTKIRQTopPriority(irq, 9); InitPort(port, baud, PARITY_NONE, 1, 8); if (HasFIFO(port)) EnableFIFO(port, 8); EnableCOMInterrupt(port, 1024 * 4); /* enable the 485 via the DTR pin */ RS485_IO_ENABLE(port); RS485_RECEIVE_ENABLE(port); #if PRINT_ENABLED_RS485 fprintf(stderr, "RS485: COM%d Enabled\r\n", port + 1); #endif return; } void RS485_Initialize( void) { #if PRINT_ENABLED_RS485 MarkTime(&RS485_Debug_Transmit_Timer); #endif RS485_Standard_Port_Settings(RS485_Port, &RS485_IRQ_Number, &RS485_Base); RS485_Open_Port(RS485_Port, RS485_Baud, RS485_Base, RS485_IRQ_Number); } void RS485_Send_Frame( volatile struct mstp_port_struct_t *mstp_port, /* port specific data */ uint8_t * buffer, /* frame to send (up to 501 bytes of data) */ uint16_t nbytes) { /* number of bytes of data (up to 501) */ bool status = true; /* return value */ /* fixme: wait turnaround time */ RS485_TRANSMIT_ENABLE(RS485_Port); SendBlock(RS485_Port, (char *) buffer, nbytes); /* need to wait at least 9600 baud * 512 bytes = 54mS */ (void) WaitSendBufferEmpty(RS485_Port, MilliSecsToTicks(200)); while (!(LineStatus(RS485_Port) & TX_SHIFT_EMPTY)) RTKScheduler(); RS485_RECEIVE_ENABLE(RS485_Port); /* SilenceTimer is cleared by the Receive State Machine when activity is detected and by the SendFrame procedure as each octet is transmitted. */ mstp_port->SilenceTimer = 0; #if PRINT_ENABLED_RS485 RS485_Print_Frame(RS485_Port, RS485_Debug_Transmit_Timer, buffer, /* frame to send (up to 501 bytes of data) */ nbytes); MarkTime(&RS485_Debug_Transmit_Timer); #endif return; } void RS485_Check_UART_Data( volatile struct mstp_port_struct_t *mstp_port) { /* port specific data */ COMData com_data = 0; /* byte from COM driver */ unsigned timeout = 1; /* milliseconds to wait for a character */ static Duration ticks = 0; /* duration to wait for data */ if (mstp_port->ReceiveError) { /* wait for state machine to clear this */ RTKScheduler(); } /* wait for state machine to read from the DataRegister */ else if (!mstp_port->DataAvailable) { if (!ticks) { ticks = MilliSecsToTicks(timeout); if (!ticks) ticks = 1; } /* check for data */ if (RTKGetTimed(ReceiveBuffer[RS485_Port], &com_data, ticks)) { /* if error, */ if (com_data & (COM_OVERRUN << 8)) mstp_port->ReceiveError = true; else if (com_data & (COM_FRAME << 8)) mstp_port->ReceiveError = true; else { mstp_port->DataRegister = com_data & 0x00FF; mstp_port->DataAvailable = true; } } } else RTKScheduler(); }