From: Robin Krens <robin@robinkrens.nl>
Date: Mon, 16 Sep 2019 09:46:16 +0000 (+0700)
Subject: st7735s: signs of life
X-Git-Url: https://robinkrens.nl/gitweb/?a=commitdiff_plain;h=a45e9d29077fac0f124a02ad75f6a7dd60218b06;p=cortex-from-scratch

st7735s: signs of life
---

diff --git a/Makefile b/Makefile
index 3eb5eed..630c2be 100644
--- a/Makefile
+++ b/Makefile
@@ -24,7 +24,7 @@ _OBJ = ivt.o systick.o sysinfo.o term.o main.o clock.o rtc.o
 OBJ = $(patsubst %, $(ODIR)/%,$(_OBJ))
 
 DDIR = obj/drivers
-_DRIVERS = uart.o tm1637.o led.o tsensor.o at24c.o mk450_joystick.o
+_DRIVERS = uart.o tm1637.o led.o tsensor.o at24c.o mk450_joystick.o st7735s.o
 DRIVERS = $(patsubst %, $(DDIR)/%,$(_DRIVERS))
 
 LDIR = obj/lib
diff --git a/drivers/st7735s.c b/drivers/st7735s.c
new file mode 100644
index 0000000..bf6c763
--- /dev/null
+++ b/drivers/st7735s.c
@@ -0,0 +1,65 @@
+/* (CC-BY-NC-SA) ROBIN KRENS - ROBIN @ ROBINKRENS.NL
+ * 
+ * $LOG$
+ * 2019/9/14 - ROBIN KRENS	
+ * Initial version 
+ * 
+ * $DESCRIPTION$
+ * 
+ * $USAGE$
+ *
+ * */
+
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+
+#include <sys/mmap.h>
+#include <sys/robsys.h>
+
+#include <lib/regfunc.h>
+#include <lib/string.h>
+#include <lib/tinyprintf.h>
+
+#include <drivers/st7735s.h>
+
+void tft_command();
+void tft_init() {
+
+	/* Peripherial init */
+	rsetbit(RCC_APB1ENR, 14); // enable SPI2
+	rsetbit(RCC_APB2ENR, 3); // enable GPIOB
+
+	/* The PINS used are respective PB12, PB13 and PB15 
+	 * NSS (or CS): alternative function pusp-pull
+	 * NSS Output is (always high) enabled with this setting
+	 * SCK Master: alternate function push-pull
+	 * MOSI (or DI): alternate function push-pull */ 
+	rwrite(GPIOB_CRH, 0xA4AA4444);
+
+	/* Chip select: software enabled */
+	rsetbit(SPI2_CR1, 9);
+	rsetbit(SPI2_CR1, 8);
+
+	// LOW and first edge: standard settings	
+
+	rsetbit(SPI2_CR1, 15); // one-wire mode
+	rsetbit(SPI2_CR1, 14); // start with transfer
+	rsetbit(SPI2_CR1, 4); // FPLCK div 8
+	rsetbit(SPI2_CR1, 2); // master selection
+	rsetbit(SPI2_CR1, 6); // enable SPI
+
+	tft_command();	
+
+}
+
+
+void tft_command() {
+
+	/* 9-bit hack */
+	uint8_t cmd = 0x0A;
+
+	rwrite(SPI2_DR, cmd);
+	while (!rchkbit(SPI2_SR, 1));
+	rclrbit(SPI2_CR1, 14); // receive
+}
diff --git a/include/drivers/st7735s.h b/include/drivers/st7735s.h
new file mode 100644
index 0000000..d345c10
--- /dev/null
+++ b/include/drivers/st7735s.h
@@ -0,0 +1,7 @@
+#ifndef __ST7735S_H
+#define __ST7735S_H
+
+extern void tft_init();
+
+#endif
+
diff --git a/include/sys/mmap.h b/include/sys/mmap.h
index 4275bc7..4af5c35 100644
--- a/include/sys/mmap.h
+++ b/include/sys/mmap.h
@@ -73,6 +73,7 @@
 #define GPIOA_CRL MEM_ADDR(0x40010800) // for ADC1
 #define GPIOA_ODR MEM_ADDR(0x4001080C)
 #define GPIOB_CRL MEM_ADDR(0x40010C00) // low register (!) for I2C1
+#define GPIOB_CRH MEM_ADDR(0x40010C04) // high register for SPI2
 #define GPIOB_BSRR MEM_ADDR(0x40010C10)
 #define GPIOB_ODR MEM_ADDR(0x40010C0C)
 #define GPIOB_IDR MEM_ADDR(0x40010C08)
@@ -85,7 +86,7 @@
 
 #define AFIO_EVCR MEM_ADDR(0x40010000)
 
-/* I2C REGISTER */
+/* I2C REGISTERS */
 #define I2C_CR1 MEM_ADDR(0x40005400)
 #define I2C_CR2 MEM_ADDR(0x40005404)
 #define I2C_DR MEM_ADDR(0x40005410)
@@ -94,6 +95,14 @@
 #define I2C_CCR MEM_ADDR(0x4000541C)
 #define I2C_TRISE MEM_ADDR(0x40005420)
 
+/* SPI2 REGISTERS */
+#define SPI2_CR1 MEM_ADDR(0x40003800)
+#define SPI2_CR2 MEM_ADDR(0x40003804)
+#define SPI2_SR MEM_ADDR(0x40003808)
+#define SPI2_DR MEM_ADDR(0x4000380C)
+#define SPI2_CFGR MEM_ADDR(0x4000381C)
+#define SPI2_PR MEM_ADDR(0x40003820)
+
 /* EXTERNAL INTERRUPTS */
 #define EXTI_IMR MEM_ADDR(0x40010400)
 #define EXTI_RTSR MEM_ADDR(0x40010408)
diff --git a/main.c b/main.c
index bcbf6f1..8de2880 100644
--- a/main.c
+++ b/main.c
@@ -26,7 +26,8 @@
 //#include <drivers/tm1637.h>
 //#include <drivers/at24c.h>
 //#include <drivers/tsensor.h>
-#include <drivers/mk450_joystick.h>
+//#include <drivers/mk450_joystick.h>
+#include <drivers/st7735s.h>
 
 void main()
 {
@@ -78,6 +79,9 @@ void main()
 	/* ADC Joystick module */
 	// mk450_init();	
 
+	/* TFT screen */
+	tft_init();
+
 	/* Start up terminal */
 	terminal();