dosbox-wii/src/hardware/serialport/directserial.cpp
2021-02-06 16:06:31 +01:00

319 lines
8.4 KiB
C++

/*
* Copyright (C) 2002-2019 The DOSBox Team
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include "dosbox.h"
#if C_DIRECTSERIAL
#include "serialport.h"
#include "directserial.h"
#include "misc_util.h"
#include "pic.h"
#include "libserial.h"
/* This is a serial passthrough class. Its amazingly simple to */
/* write now that the serial ports themselves were abstracted out */
CDirectSerial::CDirectSerial (Bitu id, CommandLine* cmd)
:CSerial (id, cmd) {
InstallationSuccessful = false;
comport = 0;
rx_retry = 0;
rx_retry_max = 0;
std::string tmpstring;
if(!cmd->FindStringBegin("realport:",tmpstring,false)) return;
LOG_MSG ("Serial%d: Opening %s", COMNUMBER, tmpstring.c_str());
if(!SERIAL_open(tmpstring.c_str(), &comport)) {
char errorbuffer[256];
SERIAL_getErrorString(errorbuffer, sizeof(errorbuffer));
LOG_MSG("Serial%d: Serial Port \"%s\" could not be opened.",
COMNUMBER, tmpstring.c_str());
LOG_MSG("%s",errorbuffer);
return;
}
#if SERIAL_DEBUG
dbgmsg_poll_block=false;
dbgmsg_rx_block=false;
#endif
// rxdelay: How many milliseconds to wait before causing an
// overflow when the application is unresponsive.
if(getBituSubstring("rxdelay:", &rx_retry_max, cmd)) {
if(!(rx_retry_max<=10000)) {
rx_retry_max=0;
}
}
CSerial::Init_Registers();
InstallationSuccessful = true;
rx_state = D_RX_IDLE;
setEvent(SERIAL_POLLING_EVENT, 1); // millisecond receive tick
}
CDirectSerial::~CDirectSerial () {
if(comport) SERIAL_close(comport);
// We do not use own events so we don't have to clear them.
}
// CanReceive: true:UART part has room left
// doReceive: true:there was really a byte to receive
// rx_retry is incremented in polling events
// in POLLING_EVENT: always add new polling event
// D_RX_IDLE + CanReceive + doReceive -> D_RX_WAIT , add RX_EVENT
// D_RX_IDLE + CanReceive + not doReceive -> D_RX_IDLE
// D_RX_IDLE + not CanReceive -> D_RX_BLOCKED, add RX_EVENT
// D_RX_BLOCKED + CanReceive + doReceive -> D_RX_FASTWAIT, rem RX_EVENT
// rx_retry=0 , add RX_EVENT
// D_RX_BLOCKED + CanReceive + !doReceive -> D_RX_IDLE, rem RX_EVENT
// rx_retry=0
// D_RX_BLOCKED + !CanReceive + doReceive + retry < max -> D_RX_BLOCKED, rx_retry++
// D_RX_BLOCKED + !CanReceive + doReceive + retry >=max -> rx_retry=0
// to be continued...
void CDirectSerial::handleUpperEvent(Bit16u type) {
switch(type) {
case SERIAL_POLLING_EVENT: {
setEvent(SERIAL_POLLING_EVENT, 1.0f);
// update Modem input line states
switch(rx_state) {
case D_RX_IDLE:
if(CanReceiveByte()) {
if(doReceive()) {
// a byte was received
rx_state=D_RX_WAIT;
setEvent(SERIAL_RX_EVENT, bytetime*0.9f);
} // else still idle
} else {
#if SERIAL_DEBUG
if(!dbgmsg_poll_block) {
log_ser(dbg_aux,"Directserial: block on polling.");
dbgmsg_poll_block=true;
}
#endif
rx_state=D_RX_BLOCKED;
// have both delays (1ms + bytetime)
setEvent(SERIAL_RX_EVENT, bytetime*0.9f);
}
break;
case D_RX_BLOCKED:
// one timeout tick
if(!CanReceiveByte()) {
rx_retry++;
if(rx_retry>=rx_retry_max) {
// it has timed out:
rx_retry=0;
removeEvent(SERIAL_RX_EVENT);
if(doReceive()) {
// read away everything
// this will set overrun errors
while(doReceive());
rx_state=D_RX_WAIT;
setEvent(SERIAL_RX_EVENT, bytetime*0.9f);
} else {
// much trouble about nothing
rx_state=D_RX_IDLE;
}
} // else wait further
} else {
// good: we can receive again
#if SERIAL_DEBUG
dbgmsg_poll_block=false;
dbgmsg_rx_block=false;
#endif
removeEvent(SERIAL_RX_EVENT);
rx_retry=0;
if(doReceive()) {
rx_state=D_RX_FASTWAIT;
setEvent(SERIAL_RX_EVENT, bytetime*0.65f);
} else {
// much trouble about nothing
rx_state=D_RX_IDLE;
}
}
break;
case D_RX_WAIT:
case D_RX_FASTWAIT:
break;
}
updateMSR();
break;
}
case SERIAL_RX_EVENT: {
switch(rx_state) {
case D_RX_IDLE:
LOG_MSG("internal error in directserial");
break;
case D_RX_BLOCKED: // try to receive
case D_RX_WAIT:
case D_RX_FASTWAIT:
if(CanReceiveByte()) {
// just works or unblocked
rx_retry=0; // not waiting anymore
if(doReceive()) {
if(rx_state==D_RX_WAIT) setEvent(SERIAL_RX_EVENT, bytetime*0.9f);
else {
// maybe unblocked
rx_state=D_RX_FASTWAIT;
setEvent(SERIAL_RX_EVENT, bytetime*0.65f);
}
} else {
// didn't receive anything
rx_state=D_RX_IDLE;
}
} else {
// blocking now or still blocked
#if SERIAL_DEBUG
if(rx_state==D_RX_BLOCKED) {
if(!dbgmsg_rx_block) {
log_ser(dbg_aux,"Directserial: rx still blocked (retry=%d)",rx_retry);
dbgmsg_rx_block=true;
}
}
else log_ser(dbg_aux,"Directserial: block on continued rx (retry=%d).",rx_retry);
#endif
setEvent(SERIAL_RX_EVENT, bytetime*0.65f);
rx_state=D_RX_BLOCKED;
}
break;
}
updateMSR();
break;
}
case SERIAL_TX_EVENT: {
// Maybe echo cirquit works a bit better this way
if(rx_state==D_RX_IDLE && CanReceiveByte()) {
if(doReceive()) {
// a byte was received
rx_state=D_RX_WAIT;
setEvent(SERIAL_RX_EVENT, bytetime*0.9f);
}
}
ByteTransmitted();
updateMSR();
break;
}
case SERIAL_THR_EVENT: {
ByteTransmitting();
setEvent(SERIAL_TX_EVENT,bytetime*1.1f);
break;
}
}
}
bool CDirectSerial::doReceive() {
int value = SERIAL_getextchar(comport);
if(value) {
receiveByteEx((Bit8u)(value&0xff),(Bit8u)((value&0xff00)>>8));
return true;
}
return false;
}
// updatePortConfig is called when emulated app changes the serial port
// parameters baudrate, stopbits, number of databits, parity.
void CDirectSerial::updatePortConfig (Bit16u divider, Bit8u lcr) {
Bit8u parity = 0;
switch ((lcr & 0x38)>>3) {
case 0x1: parity='o'; break;
case 0x3: parity='e'; break;
case 0x5: parity='m'; break;
case 0x7: parity='s'; break;
default: parity='n'; break;
}
Bit8u bytelength = (lcr & 0x3)+5;
// baudrate
Bitu baudrate;
if(divider==0) baudrate=115200;
else baudrate = 115200 / divider;
// stopbits
Bit8u stopbits;
if (lcr & 0x4) {
if (bytelength == 5) stopbits = SERIAL_15STOP;
else stopbits = SERIAL_2STOP;
} else stopbits = SERIAL_1STOP;
if(!SERIAL_setCommParameters(comport, baudrate, parity, stopbits, bytelength)) {
#if SERIAL_DEBUG
log_ser(dbg_aux,"Serial port settings not supported by host." );
#endif
LOG_MSG ("Serial%d: Desired serial mode not supported (%d,%d,%c,%d)",
COMNUMBER, baudrate,bytelength,parity,stopbits);
}
CDirectSerial::setRTSDTR(getRTS(), getDTR());
}
void CDirectSerial::updateMSR () {
int new_status = SERIAL_getmodemstatus(comport);
setCTS(new_status&SERIAL_CTS? true:false);
setDSR(new_status&SERIAL_DSR? true:false);
setRI(new_status&SERIAL_RI? true:false);
setCD(new_status&SERIAL_CD? true:false);
}
void CDirectSerial::transmitByte (Bit8u val, bool first) {
if(!SERIAL_sendchar(comport, val))
LOG_MSG("Serial%d: COM port error: write failed!", COMNUMBER);
if(first) setEvent(SERIAL_THR_EVENT, bytetime/8);
else setEvent(SERIAL_TX_EVENT, bytetime);
}
// setBreak(val) switches break on or off
void CDirectSerial::setBreak (bool value) {
SERIAL_setBREAK(comport,value);
}
// updateModemControlLines(mcr) sets DTR and RTS.
void CDirectSerial::setRTSDTR(bool rts, bool dtr) {
SERIAL_setRTS(comport,rts);
SERIAL_setDTR(comport,dtr);
}
void CDirectSerial::setRTS(bool val) {
SERIAL_setRTS(comport,val);
}
void CDirectSerial::setDTR(bool val) {
SERIAL_setDTR(comport,val);
}
#endif