Commit 5e12d436 authored by Dean Camera's avatar Dean Camera
Browse files

Remove dual ISR for software PDI mode, use a single ISR instead to reduce code complexity.

parent e322f146
...@@ -49,59 +49,53 @@ volatile uint16_t SoftUSART_Data; ...@@ -49,59 +49,53 @@ volatile uint16_t SoftUSART_Data;
#define SoftUSART_BitCount GPIOR2 #define SoftUSART_BitCount GPIOR2
/** ISR to manage the rising edge of the PDI/TPI software USART when bit-banged USART mode is selected. */ /** ISR to manage the PDI software USART when bit-banged PDI USART mode is selected. */
ISR(TIMER1_COMPA_vect, ISR_BLOCK) ISR(TIMER1_COMPA_vect, ISR_BLOCK)
{ {
/* Toggle CLOCK pin in a single cycle (see AVR datasheet) */ /* Toggle CLOCK pin in a single cycle (see AVR datasheet) */
BITBANG_PDICLOCK_PIN |= BITBANG_PDICLOCK_MASK; BITBANG_PDICLOCK_PIN |= BITBANG_PDICLOCK_MASK;
TIFR1 |= (1 << OCF1B);
TIMSK1 = (1 << OCIE1B);
/* If not sending or receiving, just exit */ /* If not sending or receiving, just exit */
if (!(SoftUSART_BitCount)) if (!(SoftUSART_BitCount))
return; return;
/* If at rising clock edge and we are in send mode, abort */ if (BITBANG_PDICLOCK_PORT & BITBANG_PDICLOCK_MASK)
if (IsSending) {
return; /* If at rising clock edge and we are in send mode, abort */
if (IsSending)
/* Wait for the start bit when receiving */ return;
if ((SoftUSART_BitCount == BITS_IN_USART_FRAME) && (BITBANG_PDIDATA_PIN & BITBANG_PDIDATA_MASK))
return; /* Wait for the start bit when receiving */
if ((SoftUSART_BitCount == BITS_IN_USART_FRAME) && (BITBANG_PDIDATA_PIN & BITBANG_PDIDATA_MASK))
/* Shift in the bit one less than the frame size in position, so that the start bit will eventually return;
* be discarded leaving the data to be byte-aligned for quick access (subtract 9 as we are ORing to the MSB) */
if (BITBANG_PDIDATA_PIN & BITBANG_PDIDATA_MASK)
((uint8_t*)&SoftUSART_Data)[1] |= (1 << (BITS_IN_USART_FRAME - 9));
SoftUSART_Data >>= 1;
SoftUSART_BitCount--;
}
/** ISR to manage the falling edge of the PDI/TPI software USART when bit-banged USART mode is selected. */ /* Shift in the bit one less than the frame size in position, so that the start bit will eventually
ISR(TIMER1_COMPB_vect, ISR_BLOCK) * be discarded leaving the data to be byte-aligned for quick access (subtract 9 as we are ORing to the MSB) */
{ if (BITBANG_PDIDATA_PIN & BITBANG_PDIDATA_MASK)
/* Toggle CLOCK pin in a single cycle (see AVR datasheet) */ ((uint8_t*)&SoftUSART_Data)[1] |= (1 << (BITS_IN_USART_FRAME - 9));
BITBANG_PDICLOCK_PIN |= BITBANG_PDICLOCK_MASK;
TIFR1 |= (1 << OCF1A);
TIMSK1 = (1 << OCIE1A);
/* If not sending or receiving, just exit */ SoftUSART_Data >>= 1;
if (!(SoftUSART_BitCount)) SoftUSART_BitCount--;
return; }
else
{
/* If not sending or receiving, just exit */
if (!(SoftUSART_BitCount))
return;
/* If at falling clock edge and we are in receive mode, abort */ /* If at falling clock edge and we are in receive mode, abort */
if (!IsSending) if (!IsSending)
return; return;
/* Set the data line to the next bit value */ /* Set the data line to the next bit value */
if (((uint8_t*)&SoftUSART_Data)[0] & 0x01) if (((uint8_t*)&SoftUSART_Data)[0] & 0x01)
BITBANG_PDIDATA_PORT |= BITBANG_PDIDATA_MASK; BITBANG_PDIDATA_PORT |= BITBANG_PDIDATA_MASK;
else else
BITBANG_PDIDATA_PORT &= ~BITBANG_PDIDATA_MASK; BITBANG_PDIDATA_PORT &= ~BITBANG_PDIDATA_MASK;
SoftUSART_Data >>= 1; SoftUSART_Data >>= 1;
SoftUSART_BitCount--; SoftUSART_BitCount--;
}
} }
/** ISR to manage the TPI software USART when bit-banged TPI USART mode is selected. */ /** ISR to manage the TPI software USART when bit-banged TPI USART mode is selected. */
...@@ -183,7 +177,6 @@ void XPROGTarget_EnableTargetPDI(void) ...@@ -183,7 +177,6 @@ void XPROGTarget_EnableTargetPDI(void)
OCR1A = BITS_BETWEEN_USART_CLOCKS; OCR1A = BITS_BETWEEN_USART_CLOCKS;
OCR1B = BITS_BETWEEN_USART_CLOCKS; OCR1B = BITS_BETWEEN_USART_CLOCKS;
TCCR1B = (1 << WGM12) | (1 << CS10); TCCR1B = (1 << WGM12) | (1 << CS10);
TCCR1C = (1 << FOC1B);
TIMSK1 = (1 << OCIE1A); TIMSK1 = (1 << OCIE1A);
#endif #endif
...@@ -253,7 +246,6 @@ void XPROGTarget_DisableTargetPDI(void) ...@@ -253,7 +246,6 @@ void XPROGTarget_DisableTargetPDI(void)
#else #else
/* Turn off software USART management timer */ /* Turn off software USART management timer */
TCCR1B = 0; TCCR1B = 0;
TCCR1C = 0;
/* Set /RESET high for a one millisecond to ensure target device is restarted */ /* Set /RESET high for a one millisecond to ensure target device is restarted */
BITBANG_PDICLOCK_PORT |= BITBANG_PDICLOCK_MASK; BITBANG_PDICLOCK_PORT |= BITBANG_PDICLOCK_MASK;
......
...@@ -57,7 +57,27 @@ ...@@ -57,7 +57,27 @@
/* Defines: */ /* Defines: */
#if ((BOARD == BOARD_XPLAIN) || (BOARD == BOARD_XPLAIN_REV1)) #if ((BOARD == BOARD_XPLAIN) || (BOARD == BOARD_XPLAIN_REV1))
#define XPROG_VIA_HARDWARE_USART // #define XPROG_VIA_HARDWARE_USART
#define BITBANG_PDIDATA_PORT PORTD
#define BITBANG_PDIDATA_DDR DDRD
#define BITBANG_PDIDATA_PIN PIND
#define BITBANG_PDIDATA_MASK (1 << 3)
#define BITBANG_PDICLOCK_PORT PORTD
#define BITBANG_PDICLOCK_DDR DDRD
#define BITBANG_PDICLOCK_PIN PIND
#define BITBANG_PDICLOCK_MASK (1 << 5)
#define BITBANG_TPIDATA_PORT PORTB
#define BITBANG_TPIDATA_DDR DDRB
#define BITBANG_TPIDATA_PIN PINB
#define BITBANG_TPIDATA_MASK (1 << 3)
#define BITBANG_TPICLOCK_PORT PORTB
#define BITBANG_TPICLOCK_DDR DDRB
#define BITBANG_TPICLOCK_PIN PINB
#define BITBANG_TPICLOCK_MASK (1 << 1)
#else #else
#define BITBANG_PDIDATA_PORT PORTB #define BITBANG_PDIDATA_PORT PORTB
#define BITBANG_PDIDATA_DDR DDRB #define BITBANG_PDIDATA_DDR DDRB
......
...@@ -66,7 +66,7 @@ MCU = at90usb1287 ...@@ -66,7 +66,7 @@ MCU = at90usb1287
# Target board (see library "Board Types" documentation, NONE for projects not requiring # Target board (see library "Board Types" documentation, NONE for projects not requiring
# LUFA board drivers). If USER is selected, put custom board drivers in a directory called # LUFA board drivers). If USER is selected, put custom board drivers in a directory called
# "Board" inside the application directory. # "Board" inside the application directory.
BOARD = USBKEY BOARD = XPLAIN
# Processor frequency. # Processor frequency.
......
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