cartreader/Cart_Reader/OSCR.cpp
2023-11-21 09:55:10 +01:00

266 lines
7.9 KiB
C++

/********************************************************************
* Open Source Cartridge Reader */
/*H******************************************************************
* FILENAME : OSCR.cpp
*
* DESCRIPTION :
* Contains various enums, variables, etc, for the main program.
*
* PUBLIC FUNCTIONS :
* void setClockScale( VOLTS )
*
* NOTES :
* This file is a WIP, I've been moving things into it on my local working
* copy, but they are not ready yet. Rather than put this in the main file
* only to move them back again, I decided to commit it early. If you need
* to add new globals, enums, defines, etc, please use this file!
*
* LICENSE :
* 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 3 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, see <https://www.gnu.org/licenses/>.
*
* CHANGES :
*
* REF NO VERSION DATE WHO DETAIL
* 12.5 2023-03-29 Ancyker Initial version
*
*H*/
#include "OSCR.h"
/*==== VARIABLES ==================================================*/
// Firmware Version
char ver[5] = "13.1";
// Clock speed
unsigned long clock = CS_16MHZ;
// Voltage
VOLTS voltage = VOLTS_SET_5V;
/*==== /VARIABLES =================================================*/
/*F******************************************************************
* NAME : void printVersionToSerial()
*
* DESCRIPTION : Prints the version & feature string to serial
*
*F*/
#if !defined(enable_serial) && defined(ENABLE_UPDATER)
void printVersionToSerial() {
ClockedSerial.print(F("OSCR"));
ClockedSerial.print(F("::"));
ClockedSerial.print(ver);
ClockedSerial.print(F("//"));
#if defined(HW1)
ClockedSerial.print(F("HW1"));
#elif defined(HW2)
ClockedSerial.print(F("HW2"));
#elif defined(HW3)
ClockedSerial.print(F("HW3"));
#elif defined(HW4)
ClockedSerial.print(F("HW4"));
#elif defined(HW5)
ClockedSerial.print(F("HW5"));
#elif defined(SERIAL_MONITOR)
ClockedSerial.print(F("Serial"));
#else
ClockedSerial.print(F("HW?"));
#endif
#if defined (ENABLE_VSELECT)
ClockedSerial.print(F("|VSELECT"));
#endif
#if defined (RTC_installed)
ClockedSerial.print(F("|RTC"));
#endif
#if defined (clockgen_installed)
ClockedSerial.print(F("|CLOCKGEN"));
#endif
#if defined (fastcrc)
ClockedSerial.print(F("|FASTCRC"));
#endif
#if defined (ENABLE_3V3FIX)
ClockedSerial.print(F("|3V3FIX"));
#endif
ClockedSerial.println(F(""));
}
#else
void printVersionToSerial() {}
#endif
/*F******************************************************************
* NAME : void setClockScale( ClockScale )
*
* DESCRIPTION : Set ATMEGA2560 clock prescaler
*
* INPUTS :
* PARAMETERS:
* VOLTS ClockScale Clock scale
*
* PROCESS :
* [1] Enable clock prescaler change
* [2] Apply clock prescaler
*
* NOTES :
* Changing the clock prescaler to a value other than F_CPU (1 by default)
* can/will result in some clock-based functions not working, including
* timers and most communication protocols.
*
* FURTHER READING :
* ATmega640/V-1280/V-1281/V-2560/V-2561/V § 10.13.2 [PDF: https://rmy.pw/atmega2560]
*
*F*/
void setClockScale(VOLTS __x)
{
uint8_t __tmp = _BV(CLKPCE); /*[1]*/
__asm__ __volatile__ (
"in __tmp_reg__,__SREG__" "\n\t"
"cli" "\n\t"
"sts %1, %0" "\n\t"
"sts %1, %2" "\n\t"
"out __SREG__, __tmp_reg__"
: /* no outputs */
: "d" (__tmp),
"M" (_SFR_MEM_ADDR(CLKPR)),
"d" (__x)
: "r0"
); /*[2]*/
}
/*F******************************************************************
* NAME : VOLTS setVoltage( Voltage )
*
* DESCRIPTION : Adjust voltage (and clock prescaler, if enabled)
*
* INPUTS :
* PARAMETERS:
* VOLTS Voltage Voltage
*
* OUTPUTS :
* RETURN :
* Type: VOLTS Result:
* Values: VOLTS_SUCCESS Successfully set the voltage/clock
* VOLTS_ERROR Something went wrong
* VOLTS_NOTENABLED VSELECT and 3V3FIX are both disabled
*
* PROCESS :
* [1] Apply voltage
* [2] Apply clock prescaler
*
* NOTES :
* When changing to 5V the voltage is set first so that the MPU
* will be stable at 16MHz. When going down to 3.3V the clock
* is changed to 8MHz first so that the MPU will be stable when
* the voltage is changed to 3.3V.
*
* This works best with VSELECT as the firmware controls the
* timing of all of this. If you are doing this manually, then
* you'll need to start the OSCR with 5V set and only switch to
* 3.3V once on the main menu.
*
*F*/
#if defined(ENABLE_VSELECT) || defined(ENABLE_3V3FIX)
VOLTS setVoltage(VOLTS newVoltage) {
switch(newVoltage) {
/* 5V */
case VOLTS_SET_5V:
if (
#if defined(ENABLE_3V3FIX)
clock == CS_16MHZ
#endif
#if defined(ENABLE_VSELECT) && defined(ENABLE_3V3FIX)
&&
#endif
#if defined(ENABLE_VSELECT)
VOLTS_SET_5V == voltage
#endif
) return VOLTS_SUCCESS; // Just return if already as requested
// Adjust voltage high if VSELECT is available
#if defined(ENABLE_VSELECT)
PORTD &= ~(1 << 7); /*[1]*/
voltage = VOLTS_SET_5V;
#endif
// Adjust clock speed when 3V3FIX is enabled
#if defined(ENABLE_3V3FIX)
// Stop serial if running
#if !defined(enable_serial) && defined(ENABLE_UPDATER)
ClockedSerial.end();
#endif
// Set clock speed
clock = CS_16MHZ;
setClockScale(newVoltage); /*[2]*/
// Restart serial
#if !defined(enable_serial) && defined(ENABLE_UPDATER)
ClockedSerial.begin(UPD_BAUD);
#endif
#else
clock = CS_16MHZ;
#endif
// Done
return VOLTS_SUCCESS;
/* 3.3V */
case VOLTS_SET_3V3:
if (
#if defined(ENABLE_3V3FIX)
clock == CS_8MHZ
#endif
#if defined(ENABLE_VSELECT) && defined(ENABLE_3V3FIX)
&&
#endif
#if defined(ENABLE_VSELECT)
VOLTS_SET_3V3 == voltage
#endif
) return VOLTS_SUCCESS; // Just return if already as requested
// Adjust clock speed when 3V3FIX is enabled
#if defined(ENABLE_3V3FIX)
#if !defined(enable_serial) && defined(ENABLE_UPDATER)
ClockedSerial.end();
#endif
// Set clock speed
clock = CS_8MHZ;
setClockScale(newVoltage); /*[2]*/
#if !defined(enable_serial) && defined(ENABLE_UPDATER)
ClockedSerial.begin(UPD_BAUD);
#endif
#endif
// Adjust voltage high if VSELECT is available
#if defined(ENABLE_VSELECT)
PORTD |= (1 << 7); /*[1]*/
voltage = VOLTS_SET_3V3;
#endif
// Done
return VOLTS_SUCCESS;
/* ??? */
default:
return VOLTS_ERROR;
}
}
#else
// The compiler will optimize this out when this condition is met.
// Yes, even though it has a return value it will only be compiled
// if something reads that value. Currently nothing does.
VOLTS setVoltage(VOLTS newVoltage __attribute__((unused))) {
return VOLTS_NOTENABLED;
}
#endif