/*
LUFA Library
- Copyright (C) Dean Camera, 2010.
+ Copyright (C) Dean Camera, 2013.
dean [at] fourwalledcubicle [dot] com
www.lufa-lib.org
*/
/*
- Copyright 2010 Dean Camera (dean [at] fourwalledcubicle [dot] com)
+ Copyright 2013 Dean Camera (dean [at] fourwalledcubicle [dot] com)
Permission to use, copy, modify, distribute, and sell this
software and its documentation for any purpose is hereby granted
advertising or publicity pertaining to distribution of the
software without specific, written prior permission.
- The author disclaim all warranties with regard to this
+ The author disclaims all warranties with regard to this
software, including all implied warranties of merchantability
and fitness. In no event shall the author be liable for any
special, indirect or consequential damages or any damages
*
* \hideinitializer
*/
-static uint8_t SPIMaskFromSCKDuration[] PROGMEM =
+static const uint8_t SPIMaskFromSCKDuration[] PROGMEM =
{
#if (F_CPU == 8000000)
SPI_SPEED_FCPU_DIV_2, // AVRStudio = 8MHz SPI, Actual = 4MHz SPI
*
* \hideinitializer
*/
-static uint16_t TimerCompareFromSCKDuration[] PROGMEM =
+static const uint16_t TimerCompareFromSCKDuration[] PROGMEM =
{
TIMER_COMP(96386), TIMER_COMP(89888), TIMER_COMP(84211), TIMER_COMP(79208), TIMER_COMP(74767),
TIMER_COMP(70797), TIMER_COMP(67227), TIMER_COMP(64000), TIMER_COMP(61069), TIMER_COMP(58395),
bool HardwareSPIMode = true;
/** Software SPI data register for sending and receiving */
-volatile uint8_t SoftSPI_Data;
+static volatile uint8_t SoftSPI_Data;
/** Number of bits left to transfer in the software SPI driver */
-volatile uint8_t SoftSPI_BitsRemaining;
+static volatile uint8_t SoftSPI_BitsRemaining;
/** ISR to handle software SPI transmission and reception */
ISR(TIMER1_COMPA_vect, ISR_BLOCK)
{
+ /* Check if rising edge (output next bit) or falling edge (read in next bit) */
if (!(PINB & (1 << 1)))
{
if (SoftSPI_Data & (1 << 7))
{
SoftSPI_Data <<= 1;
- if (!(SoftSPI_BitsRemaining--))
- TCCR1B = 0;
+ if (!(--SoftSPI_BitsRemaining))
+ {
+ TCCR1B = 0;
+ TIFR1 = (1 << OCF1A);
+ }
if (PINB & (1 << 3))
SoftSPI_Data |= (1 << 0);
PINB |= (1 << 1);
}
-/** Initialises the appropriate SPI driver (hardware or software, depending on the selected ISP speed) ready for
+/** Initializes the appropriate SPI driver (hardware or software, depending on the selected ISP speed) ready for
* communication with the attached target.
*/
void ISPTarget_EnableTargetISP(void)
DDRB |= ((1 << 1) | (1 << 2));
PORTB |= ((1 << 0) | (1 << 3));
- ISPTarget_ConfigureSoftwareISP(SCKDuration);
+ ISPTarget_ConfigureSoftwareSPI(SCKDuration);
}
}
{
if (HardwareSPIMode)
{
- SPI_ShutDown();
+ SPI_Disable();
}
else
{
DDRB &= ~((1 << 1) | (1 << 2));
PORTB &= ~((1 << 0) | (1 << 3));
-
+
+ /* Must re-enable rescue clock once software ISP has exited, as the timer for the rescue clock is
+ * re-purposed for software SPI */
ISPTarget_ConfigureRescueClock();
}
}
-/** Configures the AVR to produce a .5MHz rescue clock out of the OCR1A pin of the AVR, so
- * that it can be fed into the XTAL1 pin of an AVR whose fuses have been misconfigured for
+/** Configures the AVR to produce a 4MHz rescue clock out of the OCR1A pin of the AVR, so
+ * that it can be fed into the XTAL1 pin of an AVR whose fuses have been mis-configured for
* an external clock rather than a crystal. When used, the ISP speed must be 125KHz for this
* functionality to work correctly.
*/
#if defined(XCK_RESCUE_CLOCK_ENABLE)
/* Configure XCK as an output for the specified AVR model */
DDRD |= (1 << 5);
-
+
/* Start USART to generate a 4MHz clock on the XCK pin */
UBRR1 = ((F_CPU / 2 / ISP_RESCUE_CLOCK_SPEED) - 1);
UCSR1B = (1 << TXEN1);
#endif
}
-/** Configures the AVR's timer ready to produce software ISP for the slower ISP speeds that
+/** Configures the AVR's timer ready to produce software SPI for the slower ISP speeds that
* cannot be obtained when using the AVR's hardware SPI module.
*
* \param[in] SCKDuration Duration of the desired software ISP SCK clock
*/
-void ISPTarget_ConfigureSoftwareISP(const uint8_t SCKDuration)
+void ISPTarget_ConfigureSoftwareSPI(const uint8_t SCKDuration)
{
- /* Configure Timer 1 for software ISP using the specified SCK duration */
+ /* Configure Timer 1 for software SPI using the specified SCK duration */
TIMSK1 = (1 << OCIE1A);
TCNT1 = 0;
OCR1A = pgm_read_word(&TimerCompareFromSCKDuration[SCKDuration - sizeof(SPIMaskFromSCKDuration)]);
SoftSPI_Data = Byte;
SoftSPI_BitsRemaining = 8;
- if (SoftSPI_Data & 0x01)
+ /* Set initial MOSI pin state according to the byte to be transferred */
+ if (SoftSPI_Data & (1 << 7))
PORTB |= (1 << 2);
else
PORTB &= ~(1 << 2);
/** Asserts or deasserts the target's reset line, using the correct polarity as set by the host using a SET PARAM command.
* When not asserted, the line is tristated so as not to interfere with normal device operation.
*
- * \param[in] ResetTarget Boolean true when the target should be held in reset, false otherwise
+ * \param[in] ResetTarget Boolean true when the target should be held in reset, \c false otherwise
*/
void ISPTarget_ChangeTargetResetLine(const bool ResetTarget)
{
}
while ((ISPTarget_ReceiveByte() & 0x01) && TimeoutTicksRemaining);
- return TimeoutTicksRemaining ? STATUS_CMD_OK : STATUS_RDY_BSY_TOUT;
+ return (TimeoutTicksRemaining > 0) ? STATUS_CMD_OK : STATUS_RDY_BSY_TOUT;
}
/** Sends a low-level LOAD EXTENDED ADDRESS command to the target, for addressing of memory beyond the
{
ISPTarget_SendByte(LOAD_EXTENDED_ADDRESS_CMD);
ISPTarget_SendByte(0x00);
- ISPTarget_SendByte((CurrentAddress & 0x00FF0000) >> 16);
+ ISPTarget_SendByte(CurrentAddress >> 16);
ISPTarget_SendByte(0x00);
}
/** Waits until the last issued target memory programming command has completed, via the check mode given and using
* the given parameters.
*
- * \param[in] ProgrammingMode Programming mode used and completion check to use, a mask of PROG_MODE_* constants
+ * \param[in] ProgrammingMode Programming mode used and completion check to use, a mask of \c PROG_MODE_* constants
* \param[in] PollAddress Memory address to poll for completion if polling check mode used
* \param[in] PollValue Poll value to check against if polling check mode used
* \param[in] DelayMS Milliseconds to delay before returning if delay check mode used
while ((ISPTarget_TransferByte(0x00) == PollValue) && TimeoutTicksRemaining);
if (!(TimeoutTicksRemaining))
- ProgrammingStatus = STATUS_CMD_TOUT;
+ ProgrammingStatus = STATUS_CMD_TOUT;
break;
case PROG_MODE_WORD_READYBUSY_MASK:
break;
}
+ /* Program complete - reset timeout */
+ TimeoutTicksRemaining = COMMAND_TIMEOUT_TICKS;
+
return ProgrammingStatus;
}
projects / pub / USBasp.git / blobdiff