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Code Issues Releases Activity

Due SW SPI speedup, issue #749

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kraus
2018-11-18 21:54:22 +01:00
parent cfe78d71b6
commit d6815838b0
2 changed files with 130 additions and 0 deletions
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cppsrc/U8x8lib.cpp
+121
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@@ -517,6 +517,127 @@ extern "C" uint8_t u8x8_byte_arduino_4wire_sw_spi(u8x8_t *u8x8, uint8_t msg, uin
return 1;
}
#elif defined(__SAM3X8E__) /* Arduino DUE */
/* this function completly replaces u8x8_byte_4wire_sw_spi*/
extern "C" uint8_t u8x8_byte_arduino_4wire_sw_spi(u8x8_t *u8x8, uint8_t msg, uint8_t arg_int, void *arg_ptr)
{
uint8_t i, b;
uint16_t us = ((u8x8->display_info->sck_pulse_width_ns + 999)/1000);
uint8_t *data;
uint8_t takeover_edge = u8x8_GetSPIClockPhase(u8x8);
//uint8_t not_takeover_edge = 1 - takeover_edge;
/* the following static vars are recalculated in U8X8_MSG_BYTE_START_TRANSFER */
/* so, it should be possible to use multiple displays with different pins */
static volatile uint32_t *arduino_clock_port;
static uint32_t arduino_clock_mask;
static uint32_t arduino_clock_n_mask;
static volatile uint32_t *arduino_data_port;
static uint32_t arduino_data_mask;
static uint32_t arduino_data_n_mask;
switch(msg)
{
case U8X8_MSG_BYTE_SEND:
data = (uint8_t *)arg_ptr;
if ( takeover_edge == 0 )
{
while( arg_int > 0 )
{
b = *data;
data++;
arg_int--;
{
for( i = 0; i < 8; i++ )
{
if ( b & 128 )
*arduino_data_port |= arduino_data_mask;
else
*arduino_data_port &= arduino_data_n_mask;
//delayMicroseconds(us);
*arduino_clock_port |= arduino_clock_mask;
b <<= 1;
delayMicroseconds(us);
*arduino_clock_port &= arduino_clock_n_mask;
}
}
}
}
else
{
while( arg_int > 0 )
{
b = *data;
data++;
arg_int--;
{
for( i = 0; i < 8; i++ )
{
if ( b & 128 )
*arduino_data_port |= arduino_data_mask;
else
*arduino_data_port &= arduino_data_n_mask;
//delayMicroseconds(us);
*arduino_clock_port &= arduino_clock_n_mask;
b <<= 1;
delayMicroseconds(us);
*arduino_clock_port |= arduino_clock_mask;
}
}
}
}
break;
case U8X8_MSG_BYTE_INIT:
/* disable chipselect */
u8x8_gpio_SetCS(u8x8, u8x8->display_info->chip_disable_level);
/* no wait required here */
/* for SPI: setup correct level of the clock signal */
u8x8_gpio_SetSPIClock(u8x8, u8x8_GetSPIClockPhase(u8x8));
break;
case U8X8_MSG_BYTE_SET_DC:
u8x8_gpio_SetDC(u8x8, arg_int);
break;
case U8X8_MSG_BYTE_START_TRANSFER:
u8x8_gpio_SetCS(u8x8, u8x8->display_info->chip_enable_level);
u8x8->gpio_and_delay_cb(u8x8, U8X8_MSG_DELAY_NANO, u8x8->display_info->post_chip_enable_wait_ns, NULL);
/* there is no consistency checking for u8x8->pins[U8X8_PIN_SPI_CLOCK] */
arduino_clock_port = portOutputRegister(digitalPinToPort(u8x8->pins[U8X8_PIN_SPI_CLOCK]));
arduino_clock_mask = digitalPinToBitMask(u8x8->pins[U8X8_PIN_SPI_CLOCK]);
arduino_clock_n_mask = ~arduino_clock_mask;
/* there is no consistency checking for u8x8->pins[U8X8_PIN_SPI_DATA] */
arduino_data_port = portOutputRegister(digitalPinToPort(u8x8->pins[U8X8_PIN_SPI_DATA]));
arduino_data_mask = digitalPinToBitMask(u8x8->pins[U8X8_PIN_SPI_DATA]);
arduino_data_n_mask = ~arduino_data_mask;
break;
case U8X8_MSG_BYTE_END_TRANSFER:
u8x8->gpio_and_delay_cb(u8x8, U8X8_MSG_DELAY_NANO, u8x8->display_info->pre_chip_disable_wait_ns, NULL);
u8x8_gpio_SetCS(u8x8, u8x8->display_info->chip_disable_level);
break;
default:
return 0;
}
return 1;
}
#else
/* fallback */
uint8_t u8x8_byte_arduino_4wire_sw_spi(u8x8_t *u8x8, uint8_t msg, uint8_t arg_int, void *arg_ptr)