1 /* (CC-BY-NC-SA) ROBIN KRENS - ROBIN @ ROBINKRENS.NL
4 * 2019/9/14 - ROBIN KRENS
19 #include <sys/robsys.h>
21 #include <lib/regfunc.h>
22 #include <lib/string.h>
23 #include <lib/tinyprintf.h>
24 #include <lib/fonts/wogfont.h>
26 #include <drivers/st7735s.h>
33 #define XPOS(x) (x * 6)
34 #define YPOS(y) (y * 8)
50 tftscreen.textmemptr = tftscreen.buf;
52 memset(tftscreen.buf, 0x00, 352);
54 /* Peripherial init */
55 rsetbit(RCC_APB1ENR, 14); // enable SPI2
56 rsetbit(RCC_APB2ENR, 3); // enable GPIOB
57 rsetbit(RCC_APB2ENR, 4); // enable GPIOC
59 /* The PINS used are PB12, PB13, PB15 and PC6 respectively
60 * NSS (or CS): alternative function pusp-pull
61 * NSS Output is (always high) enabled with this setting
62 * SCK Master: alternate function push-pull
63 * MOSI (or DI): alternate function push-pull
64 * D/CX (or A0): Command or data write line PC6 */
65 rwrite(GPIOB_CRH, 0xA4AA4444);
66 rwrite(GPIOC_CRL, 0x42444444);
68 /* Chip select: software enabled
69 * In case for a hardware setup, connect NSS (CS) to
74 rsetbit(SPI2_CR1, 15); // one-wire mode
75 rsetbit(SPI2_CR1, 14); // start with transfer
76 rsetbit(SPI2_CR1, 4); // FPLCK div 8
77 rsetbit(SPI2_CR1, 2); // master selection
78 rsetbit(SPI2_CR1, 6); // enable SPI
81 tft_command(TFT_SWRESET, 0);
86 /* Frame rate control */
87 tft_command(TFT_FRMCTR1, 3, 0x01, 0x2C, 0x2D);
88 tft_command(TFT_FRMCTR2, 3, 0x01, 0x2C, 0x2D);
89 tft_command(TFT_FRMCTR3, 6, 0x01, 0x2C, 0x2D, 0x01, 0x2C, 0x2D);
92 tft_command(TFT_PWCTR1, 3, 0xA2, 0x02, 0x84);
93 tft_command(TFT_PWCTR2, 1, 0xC5);
94 tft_command(TFT_PWCTR3, 2, 0x0A, 0x00);
95 tft_command(TFT_PWCTR4, 2, 0x8A, 0x2A);
96 tft_command(TFT_PWCTR5, 2, 0x8A, 0xEE);
97 tft_command(TFT_VMCTR1, 1, 0x0E);
99 tft_command(TFT_INVOFF, 0);
100 tft_command(TFT_COLMOD, 1, 0x05); // 0x05
101 tft_command(TFT_MADCTL, 1, 0xC0); // TODO: check
103 tft_command(TFT_CASET, 4, 0x00, 0x00, 0x00, 0x7F);
104 tft_command(TFT_RASET, 4, 0x00, 0x00, 0x00, 0x9F);
107 tft_command(TFT_GMCTRP1, 16, 0x02, 0x1C, 0x07, 0x12,
108 0x37, 0x32, 0x29, 0x2D,
109 0x29, 0x25, 0x2B, 0x39,
110 0x00, 0x01, 0x03, 0x10);
111 tft_command(TFT_GMCTRN1, 16, 0x03, 0x1D, 0x07, 0x06,
112 0x2E, 0x2C, 0x29, 0x2D,
113 0x2E, 0x2E, 0x37, 0x3F,
114 0x00, 0x00, 0x02, 0x10);
116 /* Before turning on the display, fill the display
117 * so no random display data is shown */
118 tft_fill(0,0,SCRWIDTH-1,SCRHEIGHT-1,0x0000);
121 tft_command(TFT_NORON, 0);
123 tft_command(TFT_DISPON, 0);
128 /* Helper function */
129 static int txbuf_empty () {
131 while(!rchkbit(SPI2_SR, 1)) {
134 printf("Error: transmit timeout!\n");
143 /* Function to fill an area starting at (beginx, beginy)
144 * and end ending at (endx, endy */
145 int tft_fill(uint8_t beginx, uint8_t beginy, uint8_t endx,
146 uint8_t endy, uint16_t color) {
148 /* The CASET and RASET commands set the begin X/Y
149 * and end X/Y of the fill area. Both are split over
150 * two paramters/bytes. Most screen are small, so you will
151 * only need to consider the first 8 MSBs. Parameter 1 and
154 * In theory, TFT screens of 65,535 by 65,535 could be
156 tft_command(TFT_CASET, 4, 0x00, beginx, 0x00, endx);
157 tft_command(TFT_RASET, 4, 0x00, beginy, 0x00, endy);
159 /* After setting the fill area, we can send the color
160 * data. The chip autoincrements the address so we can
161 * keep writing continiously for the fill area. Note
162 * that each pixel requires two bytes to be send (16
164 uint32_t totalwrites = (endx - beginx) * (endy - beginy) * 2;
165 //printf("tw: %d, x: %d, y: %d\n", totalwrites, beginx, beginy);
166 tft_command(TFT_RAMWR, 0);
167 rsetbit(GPIOC_ODR, 6); // data = 1
168 for (int i = 0; i < totalwrites; i++) {
169 rwrite(SPI2_DR, (uint8_t) (color >> 8));
172 rwrite(SPI2_DR, (uint8_t) (color & 0xFF));
179 /* Function to individually set a pixel
180 * Refer to tft_fill, similar calls */
181 int tft_setpixel(uint8_t x, uint8_t y, uint16_t color) {
183 tft_command(TFT_CASET, 4, 0x00, x, 0x00, x+1);
184 tft_command(TFT_RASET, 4, 0x00, y, 0x00, y+1);
185 tft_command(TFT_RAMWR, 2, (uint8_t) (color >> 8), (uint8_t) (color & 0xFF));
190 int tft_puts(char * str) {
192 for (int i = 0; i < strlen(str); i++) {
193 tft_putc(0xFFFF, 0x0000, str[i]);
202 tftscreen.buf[BUFFER - 21] = '\0';
203 tftscreen.cpos -= 21;
207 /* Text scroll function
208 * Refeed the buffer */
211 /* Scroll the buffer */
212 memcpy(tftscreen.textmemptr, tftscreen.textmemptr + 21, BUFFER - 21);
213 for (int i = 21; i >= 0; i--)
214 tftscreen.buf[BUFFER - 21] = '\0';
220 tft_puts(tftscreen.buf); // CHECK: ending
224 void tft_linefill() {
230 /* Low-level function to print a character to the display
231 * Should not be used directly */
232 int tft_putc(uint16_t fg, uint16_t bg, int c) {
235 int totalpixels = 35;
240 if (tftscreen.y >= 15) {
244 tft_command(TFT_CASET, 4, 0x00, STARTX + XPOS(tftscreen.x), 0x00, (STARTX + 4) + XPOS(tftscreen.x));
245 tft_command(TFT_RASET, 4, 0x00, STARTY + YPOS(tftscreen.y), 0x00, (STARTY + 6) + YPOS(tftscreen.y));
247 tft_command(TFT_RAMWR, 0);
248 rsetbit(GPIOC_ODR, 6); // data = 1
249 for (int i = 0; i < totalpixels; i++) {
251 current = ASCII5x7[(c * 5) + column];
253 if ((current >> (7 - row)) & 0x1) {
254 rwrite(SPI2_DR, (uint8_t) (fg >> 8));
257 rwrite(SPI2_DR, (uint8_t) (fg & 0xFF));
262 rwrite(SPI2_DR, (uint8_t) (bg >> 8));
265 rwrite(SPI2_DR, (uint8_t) (bg & 0xFF));
270 /* Algoritm dependent on draw mode: top down, left right */
277 tftscreen.buf[tftscreen.cpos] = c;
281 if (tftscreen.x > 20) {
291 /* Invokes commands with a variable list of paramaters. Sending parameters
292 * requires the D/CX line to be high */
293 int tft_command(uint8_t cmd, int argsc, ...) {
297 rclrbit(GPIOC_ODR, 6); // D/CX line low
298 rwrite(SPI2_DR, cmd);
305 rsetbit(GPIOC_ODR, 6); // D/CX line high
306 for (int i = 0; i < argsc; i++) {
307 uint8_t p = (uint8_t) va_arg(ap, unsigned int);