summaryrefslogtreecommitdiff
path: root/software/led_fade
diff options
context:
space:
mode:
authorMegan Wachs <megan@sifive.com>2017-01-10 14:50:23 -0800
committerGitHub <noreply@github.com>2017-01-10 14:50:23 -0800
commit57983086991b12a0c8caf707e5f0b810c3a49647 (patch)
tree08e00e8dffd3fb20fe63ae297ac17cff6c4545b4 /software/led_fade
parentd69f4cb8653f4974374f98debf9ce2cc820a2b57 (diff)
parent12d8daf1cacf8754e828ba0713a43500d8f9d128 (diff)
Merge pull request #44 from sifive/led_fade_demo
Add the led_fade demo which ships on HiFive1 boards
Diffstat (limited to 'software/led_fade')
-rw-r--r--software/led_fade/Makefile6
-rw-r--r--software/led_fade/led_fade.c160
2 files changed, 166 insertions, 0 deletions
diff --git a/software/led_fade/Makefile b/software/led_fade/Makefile
new file mode 100644
index 0000000..c42049b
--- /dev/null
+++ b/software/led_fade/Makefile
@@ -0,0 +1,6 @@
+TARGET = led_fade
+C_SRCS += led_fade.c
+CFLAGS += -O2 -fno-builtin-printf
+
+BSP_BASE = ../../bsp
+include $(BSP_BASE)/env/common.mk
diff --git a/software/led_fade/led_fade.c b/software/led_fade/led_fade.c
new file mode 100644
index 0000000..775647a
--- /dev/null
+++ b/software/led_fade/led_fade.c
@@ -0,0 +1,160 @@
+// See LICENSE for license details.
+
+// This is the program which ships on the HiFive1
+// board, executing out of SPI Flash at 0x20400000.
+
+#include <stdint.h>
+#include "platform.h"
+
+static const char led_msg[] = "\a\n\r\n\r\
+55555555555555555555555555555555555555555555555\n\r\
+5555555 Are the LEDs Changing? [y/n] 555555555\n\r\
+55555555555555555555555555555555555555555555555\n\r";
+
+static const char sifive_msg[] = "\n\r\
+\n\r\
+ SIFIVE, INC.\n\r\
+\n\r\
+ 5555555555555555555555555\n\r\
+ 5555 5555\n\r\
+ 5555 5555\n\r\
+ 5555 5555\n\r\
+ 5555 5555555555555555555555\n\r\
+ 5555 555555555555555555555555\n\r\
+ 5555 5555\n\r\
+ 5555 5555\n\r\
+ 5555 5555\n\r\
+5555555555555555555555555555 55555\n\r\
+ 55555 555555555 55555\n\r\
+ 55555 55555 55555\n\r\
+ 55555 5 55555\n\r\
+ 55555 55555\n\r\
+ 55555 55555\n\r\
+ 55555 55555\n\r\
+ 55555 55555\n\r\
+ 55555 55555\n\r\
+ 555555555\n\r\
+ 55555\n\r\
+ 5\n\r\
+\n\r\
+ 'led_fade' Demo \n\r\
+\n\r";
+
+static void _putc(char c) {
+ while ((int32_t) UART0_REG(UART_REG_TXFIFO) < 0);
+ UART0_REG(UART_REG_TXFIFO) = c;
+}
+
+int _getc(char * c){
+ int32_t val = (int32_t) UART0_REG(UART_REG_RXFIFO);
+ if (val > 0) {
+ *c = val & 0xFF;
+ return 1;
+ }
+ return 0;
+}
+
+
+static void _puts(const char * s) {
+ while (*s != '\0'){
+ _putc(*s++);
+ }
+}
+
+
+int main (void){
+
+ // Run off 16 MHz Crystal for accuracy.
+ PRCI_REG(PRCI_PLLCFG) = (PLL_REFSEL(1) | PLL_BYPASS(1));
+ PRCI_REG(PRCI_PLLCFG) |= (PLL_SEL(1));
+ // Turn off HFROSC to save power
+ PRCI_REG(PRCI_HFROSCCFG) = 0;
+
+ // Configure UART to print
+ GPIO_REG(GPIO_OUTPUT_VAL) |= IOF0_UART0_MASK;
+ GPIO_REG(GPIO_OUTPUT_EN) |= IOF0_UART0_MASK;
+ GPIO_REG(GPIO_IOF_SEL) &= ~IOF0_UART0_MASK;
+ GPIO_REG(GPIO_IOF_EN) |= IOF0_UART0_MASK;
+
+ // 115200 Baud Rate
+ UART0_REG(UART_REG_DIV) = 138;
+ UART0_REG(UART_REG_TXCTRL) = UART_TXEN;
+ UART0_REG(UART_REG_RXCTRL) = UART_RXEN;
+
+ // Wait a bit to avoid corruption on the UART.
+ // (In some cases, switching to the IOF can lead
+ // to output glitches, so need to let the UART
+ // reciever time out and resynchronize to the real
+ // start of the stream.
+ volatile int i=0;
+ while(i < 10000){i++;}
+
+ _puts(sifive_msg);
+ //_puts("Config String:\n\r");
+ //_puts(*((const char **) 0x100C));
+ //_puts("\n\r");
+ _puts(led_msg);
+
+ uint16_t r=0xFF;
+ uint16_t g=0;
+ uint16_t b=0;
+ char c = 0;
+
+ // Set up RGB PWM
+
+ PWM1_REG(PWM_CFG) = 0;
+ // To balance the power consumption, make one left, one right, and one center aligned.
+ PWM1_REG(PWM_CFG) = (PWM_CFG_ENALWAYS) | (PWM_CFG_CMP2CENTER);
+ PWM1_REG(PWM_COUNT) = 0;
+
+ // Period is approximately 244 Hz
+ // the LEDs are intentionally left somewhat dim,
+ // as the full brightness can be painful to look at.
+ PWM1_REG(PWM_CMP0) = 0;
+
+ GPIO_REG(GPIO_IOF_SEL) |= ( (1 << GREEN_LED_OFFSET) | (1 << BLUE_LED_OFFSET) | (1 << RED_LED_OFFSET));
+ GPIO_REG(GPIO_IOF_EN ) |= ( (1 << GREEN_LED_OFFSET) | (1 << BLUE_LED_OFFSET) | (1 << RED_LED_OFFSET));
+ GPIO_REG(GPIO_OUTPUT_XOR) &= ~( (1 << GREEN_LED_OFFSET) | (1 << BLUE_LED_OFFSET));
+ GPIO_REG(GPIO_OUTPUT_XOR) |= (1 << RED_LED_OFFSET);
+
+ while(1){
+ volatile uint64_t * now = (volatile uint64_t*)(CLINT_BASE_ADDR + CLINT_MTIME);
+ volatile uint64_t then = *now + 100;
+ while (*now < then) { }
+
+ if(r > 0 && b == 0){
+ r--;
+ g++;
+ }
+ if(g > 0 && r == 0){
+ g--;
+ b++;
+ }
+ if(b > 0 && g == 0){
+ r++;
+ b--;
+ }
+
+ uint32_t G = g;
+ uint32_t R = r;
+ uint32_t B = b;
+
+ PWM1_REG(PWM_CMP1) = G << 4; // PWM is low on the left, GPIO is low on the left side, LED is ON on the left.
+ PWM1_REG(PWM_CMP2) = (B << 1) << 4; // PWM is high on the middle, GPIO is low in the middle, LED is ON in the middle.
+ PWM1_REG(PWM_CMP3) = 0xFFFF - (R << 4); // PWM is low on the left, GPIO is low on the right, LED is on on the right.
+
+ // Check for user input
+ if (c == 0){
+ if (_getc(&c) != 0){
+ _putc(c);
+ _puts("\n\r");
+
+ if ((c == 'y') || (c == 'Y')){
+ _puts("PASS\n\r");
+ } else{
+ _puts("FAIL\n\r");
+ }
+ }
+ }
+ }
+}