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authorchrysn2012-10-17 18:55:54 +0200
committerchrysn2012-10-17 18:55:54 +0200
commit7c33025c318bcc43cfcd3a23a76d14b299fecc0a (patch)
tree491adcf9ada616f15c435929e878c5ca3cddc568 /examples/stm32/f4/stm32f4-discovery
parenta69d83d312396ee604426dce5341a54316c7c9b5 (diff)
parent0a483449654e18189ff017f70d6b97888cdba382 (diff)
Merge branch 'master' into generalizations
Conflicts: lib/lm3s/vector.c -- split out to lm3s/irq.h lib/stm32/f4/vector.c -- put the floating point initialization code into a function like in lpc43xx
Diffstat (limited to 'examples/stm32/f4/stm32f4-discovery')
-rw-r--r--examples/stm32/f4/stm32f4-discovery/mandelbrot/Makefile25
-rw-r--r--examples/stm32/f4/stm32f4-discovery/mandelbrot/README12
-rw-r--r--examples/stm32/f4/stm32f4-discovery/mandelbrot/mandel.c127
-rw-r--r--examples/stm32/f4/stm32f4-discovery/random/Makefile25
-rw-r--r--examples/stm32/f4/stm32f4-discovery/random/README5
-rw-r--r--examples/stm32/f4/stm32f4-discovery/random/random.c88
6 files changed, 282 insertions, 0 deletions
diff --git a/examples/stm32/f4/stm32f4-discovery/mandelbrot/Makefile b/examples/stm32/f4/stm32f4-discovery/mandelbrot/Makefile
new file mode 100644
index 0000000..3879eca
--- /dev/null
+++ b/examples/stm32/f4/stm32f4-discovery/mandelbrot/Makefile
@@ -0,0 +1,25 @@
+##
+## This file is part of the libopencm3 project.
+##
+## Copyright (C) 2009 Uwe Hermann <uwe@hermann-uwe.de>
+##
+## This library is free software: you can redistribute it and/or modify
+## it under the terms of the GNU Lesser General Public License as published by
+## the Free Software Foundation, either version 3 of the License, or
+## (at your option) any later version.
+##
+## This library 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 Lesser General Public License for more details.
+##
+## You should have received a copy of the GNU Lesser General Public License
+## along with this library. If not, see <http://www.gnu.org/licenses/>.
+##
+
+BINARY = mandel
+
+LDSCRIPT = ../stm32f4-discovery.ld
+
+include ../../Makefile.include
+
diff --git a/examples/stm32/f4/stm32f4-discovery/mandelbrot/README b/examples/stm32/f4/stm32f4-discovery/mandelbrot/README
new file mode 100644
index 0000000..fe4fb13
--- /dev/null
+++ b/examples/stm32/f4/stm32f4-discovery/mandelbrot/README
@@ -0,0 +1,12 @@
+------------------------------------------------------------------------------
+README
+------------------------------------------------------------------------------
+
+This example program demonstrates the floating point coprocessor usage on
+the ST STM32F4DISCOVERY eval board.
+
+A mandelbrot fractal is calculated and sent as "ascii-art" image through
+the USART2.
+
+The terminal settings for the receiving device/PC are 38400 8n1.
+
diff --git a/examples/stm32/f4/stm32f4-discovery/mandelbrot/mandel.c b/examples/stm32/f4/stm32f4-discovery/mandelbrot/mandel.c
new file mode 100644
index 0000000..5cbdafd
--- /dev/null
+++ b/examples/stm32/f4/stm32f4-discovery/mandelbrot/mandel.c
@@ -0,0 +1,127 @@
+/*
+ * This file is part of the libopencm3 project.
+ *
+ * Copyright (C) 2009 Uwe Hermann <uwe@hermann-uwe.de>
+ * Copyright (C) 2011 Stephen Caudle <scaudle@doceme.com>
+ * Copyright (C) 2012 Daniel Serpell <daniel.serpell@gmail.com>
+ *
+ * This library is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This library 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 Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <libopencm3/stm32/f4/rcc.h>
+#include <libopencm3/stm32/f4/gpio.h>
+#include <libopencm3/stm32/usart.h>
+
+void clock_setup(void)
+{
+ /* Enable high-speed clock at 120MHz */
+ rcc_clock_setup_hse_3v3(&hse_8mhz_3v3[CLOCK_3V3_120MHZ]);
+
+ /* Enable GPIOD clock for LED & USARTs. */
+ rcc_peripheral_enable_clock(&RCC_AHB1ENR, RCC_AHB1ENR_IOPDEN);
+ rcc_peripheral_enable_clock(&RCC_AHB1ENR, RCC_AHB1ENR_IOPAEN);
+
+ /* Enable clocks for USART2. */
+ rcc_peripheral_enable_clock(&RCC_APB1ENR, RCC_APB1ENR_USART2EN);
+}
+
+void usart_setup(void)
+{
+ /* Setup USART2 parameters. */
+ usart_set_baudrate(USART2, 38400);
+ usart_set_databits(USART2, 8);
+ usart_set_stopbits(USART2, USART_STOPBITS_1);
+ usart_set_mode(USART2, USART_MODE_TX);
+ usart_set_parity(USART2, USART_PARITY_NONE);
+ usart_set_flow_control(USART2, USART_FLOWCONTROL_NONE);
+
+ /* Finally enable the USART. */
+ usart_enable(USART2);
+}
+
+void gpio_setup(void)
+{
+ /* Setup GPIO pin GPIO12 on GPIO port D for LED. */
+ gpio_mode_setup(GPIOD, GPIO_MODE_OUTPUT, GPIO_PUPD_NONE, GPIO12);
+
+ /* Setup GPIO pins for USART2 transmit. */
+ gpio_mode_setup(GPIOA, GPIO_MODE_AF, GPIO_PUPD_NONE, GPIO2);
+
+ /* Setup USART2 TX pin as alternate function. */
+ gpio_set_af(GPIOA, GPIO_AF7, GPIO2);
+}
+
+/* Maximum number of iterations for the escape-time calculation */
+#define maxIter 32
+/* This array converts the iteration count to a character representation. */
+static char color[maxIter+1] = " .:++xxXXX%%%%%%################";
+
+/* Main mandelbrot calculation */
+static int iterate(float px, float py)
+{
+ int it=0;
+ float x=0,y=0;
+ while(it<maxIter)
+ {
+ float nx = x*x;
+ float ny = y*y;
+ if( (nx + ny) > 4 )
+ return it;
+ // Zn+1 = Zn^2 + P
+ y = 2*x*y + py;
+ x = nx - ny + px;
+ it++;
+ }
+ return 0;
+}
+
+static void mandel(float cX, float cY, float scale)
+{
+ int x,y;
+ for(x=-60;x<60;x++)
+ {
+ for(y=-50;y<50;y++)
+ {
+ int i = iterate(cX+x*scale, cY+y*scale);
+ usart_send_blocking(USART2, color[i]);
+ }
+ usart_send_blocking(USART2, '\r');
+ usart_send_blocking(USART2, '\n');
+ }
+}
+
+int main(void)
+{
+ float scale = 0.25f, centerX = -0.5f, centerY = 0.0f;
+
+ clock_setup();
+ gpio_setup();
+ usart_setup();
+
+ while (1) {
+ /* Blink the LED (PD12) on the board with each fractal drawn. */
+ gpio_toggle(GPIOD, GPIO12); /* LED on/off */
+ mandel(centerX,centerY,scale); /* draw mandelbrot */
+
+ /* Change scale and center */
+ centerX += 0.175f * scale;
+ centerY += 0.522f * scale;
+ scale *= 0.875f;
+
+ usart_send_blocking(USART2, '\r');
+ usart_send_blocking(USART2, '\n');
+ }
+
+ return 0;
+}
diff --git a/examples/stm32/f4/stm32f4-discovery/random/Makefile b/examples/stm32/f4/stm32f4-discovery/random/Makefile
new file mode 100644
index 0000000..4f06835
--- /dev/null
+++ b/examples/stm32/f4/stm32f4-discovery/random/Makefile
@@ -0,0 +1,25 @@
+##
+## This file is part of the libopencm3 project.
+##
+## Copyright (C) 2009 Uwe Hermann <uwe@hermann-uwe.de>
+##
+## This library is free software: you can redistribute it and/or modify
+## it under the terms of the GNU Lesser General Public License as published by
+## the Free Software Foundation, either version 3 of the License, or
+## (at your option) any later version.
+##
+## This library 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 Lesser General Public License for more details.
+##
+## You should have received a copy of the GNU Lesser General Public License
+## along with this library. If not, see <http://www.gnu.org/licenses/>.
+##
+
+BINARY = random
+
+LDSCRIPT = ../stm32f4-discovery.ld
+
+include ../../Makefile.include
+
diff --git a/examples/stm32/f4/stm32f4-discovery/random/README b/examples/stm32/f4/stm32f4-discovery/random/README
new file mode 100644
index 0000000..875e6bf
--- /dev/null
+++ b/examples/stm32/f4/stm32f4-discovery/random/README
@@ -0,0 +1,5 @@
+------------------------------------------------------------------------------
+README
+------------------------------------------------------------------------------
+
+This example randomly blinks the green LED on the ST STM32F4DISCOVERY eval board.
diff --git a/examples/stm32/f4/stm32f4-discovery/random/random.c b/examples/stm32/f4/stm32f4-discovery/random/random.c
new file mode 100644
index 0000000..9305be3
--- /dev/null
+++ b/examples/stm32/f4/stm32f4-discovery/random/random.c
@@ -0,0 +1,88 @@
+/*
+ * This file is part of the libopencm3 project.
+ *
+ * This library is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This library 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 Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+
+#include <libopencm3/cm3/common.h>
+#include <libopencm3/stm32/f4/rcc.h>
+#include <libopencm3/stm32/f4/gpio.h>
+#include <libopencm3/stm32/f4/rng.h>
+
+static void rcc_setup(void)
+{
+ rcc_clock_setup_hse_3v3(&hse_8mhz_3v3[CLOCK_3V3_120MHZ]);
+
+ /* Enable GPIOD clock for onboard leds. */
+ rcc_peripheral_enable_clock(&RCC_AHB1ENR, RCC_AHB1ENR_IOPDEN);
+
+ /* Enable rng clock */
+ rcc_peripheral_enable_clock(&RCC_AHB2ENR, RCC_AHB2ENR_RNGEN);
+}
+
+static void rng_setup(void)
+{
+ /* Enable interupt */
+ /* Set the IE bit in the RNG_CR register. */
+ RNG_CR |= RNG_CR_IE;
+ /* Enable the random number generation by setting the RNGEN bit in the RNG_CR
+ register. This activates the analog part, the RNG_LFSR and the error detector.
+ */
+ RNG_CR |= RNG_CR_EN;
+}
+
+static void gpio_setup(void)
+{
+ /* Setup onboard led */
+ gpio_mode_setup(GPIOD, GPIO_MODE_OUTPUT, GPIO_PUPD_NONE, GPIO12 | GPIO13);
+}
+
+/* Tried to folow the guidelines in the stm32f4 user manual.*/
+static u32 random_int(void)
+{
+ static u32 last_value=0;
+ static u32 new_value=0;
+ u32 error_bits = 0;
+ error_bits = RNG_SR_SEIS | RNG_SR_CEIS;
+ while (new_value==last_value) {
+ /* Check for error flags and if data is ready. */
+ if ( ((RNG_SR & error_bits) == 0) && ( (RNG_SR & RNG_SR_DRDY) == 1 ) )
+ new_value=RNG_DR;
+ }
+ last_value=new_value;
+ return new_value;
+}
+
+
+int main(void)
+{
+ int i,j;
+ rcc_setup();
+ gpio_setup();
+ rng_setup();
+ while(1){
+ u32 rnd;
+ rnd = random_int();
+ for(i=0;i!=32;++i){
+ if ( (rnd & (1 << i))!=0 )
+ gpio_set(GPIOD, GPIO12);
+ else
+ gpio_clear(GPIOD, GPIO12);
+ /* Delay */
+ for(j=0;j!=5000000;++j)
+ __asm__("nop");
+ }
+ }
+}