--- /dev/null
+/*
+ * Copyright © 2023 Keith Packard <keithp@keithp.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+#include <ao.h>
+#include <ao_st7565.h>
+
+static void
+ao_st7565_reset(void)
+{
+ ao_gpio_set(AO_ST7565_RESET_PORT, AO_ST7565_RESET_PIN, 0);
+ ao_delay(AO_MS_TO_TICKS(100));
+ ao_gpio_set(AO_ST7565_RESET_PORT, AO_ST7565_RESET_PIN, 1);
+ ao_delay(AO_MS_TO_TICKS(100));
+}
+
+
+static void
+ao_st7565_start(uint8_t a0)
+{
+ ao_gpio_set(AO_ST7565_A0_PORT, AO_ST7565_A0_PIN, a0);
+ ao_spi_get_bit(AO_ST7565_CS_PORT,
+ AO_ST7565_CS_PIN,
+ AO_ST7565_SPI_BUS,
+ AO_ST7565_SPI_SPEED);
+}
+
+static void
+ao_st7565_stop(void)
+{
+ ao_spi_put_bit(AO_ST7565_CS_PORT,
+ AO_ST7565_CS_PIN,
+ AO_ST7565_SPI_BUS);
+ ao_gpio_set(AO_ST7565_A0_PORT, AO_ST7565_A0_PIN, 1);
+}
+
+
+static void
+ao_st7565_instruction(uint8_t cmd)
+{
+ ao_st7565_start(0);
+ ao_spi_send(&cmd, 1, AO_ST7565_SPI_BUS);
+ ao_st7565_stop();
+}
+
+static void
+ao_st7565_instruction_param(uint8_t cmd, uint8_t param)
+{
+ uint8_t b[2] = { cmd, param };
+ ao_st7565_start(0);
+ ao_spi_send(b, 2, AO_ST7565_SPI_BUS);
+ ao_st7565_stop();
+}
+
+static void
+ao_st7565_instructions(const uint8_t *cmd, uint16_t len)
+{
+ ao_st7565_start(0);
+ ao_spi_send(cmd, len, AO_ST7565_SPI_BUS);
+ ao_st7565_stop();
+}
+
+static void
+ao_st7565_data(const void *base, uint16_t len)
+{
+ ao_st7565_start(1);
+ ao_spi_send(base, len, AO_ST7565_SPI_BUS);
+ ao_st7565_stop();
+}
+
+static uint8_t brightness;
+
+void
+ao_st7565_set_brightness(uint8_t val)
+{
+ if (val > 63)
+ val = 63;
+ brightness = val;
+ ao_st7565_instruction_param(ST7565_ELECTRONIC_VOLUME_SET, val);
+}
+
+uint8_t
+ao_st7565_get_brightness(void)
+{
+ return brightness;
+}
+
+static bool setup_done;
+
+static void
+ao_st7565_setup(void)
+{
+ static const uint8_t init[] = {
+ /*
+ * Should be set to one of ST7565_LCD_BIAS_1_9 or
+ * ST7565_LCD_BIAS_1_7
+ */
+ AO_ST7565_BIAS,
+ ST7565_ADC_SELECT_NORMAL,
+ ST7565_COMMON_MODE_NORMAL,
+ ST7565_DISPLAY_START_LINE_SET(0),
+ ST7565_POWER_CONTROL_SET(0x4),
+ };
+
+ if (setup_done)
+ return;
+ setup_done = true;
+ ao_st7565_reset();
+ ao_st7565_instructions(init, sizeof(init));
+ ao_delay(AO_MS_TO_TICKS(50));
+ ao_st7565_instruction(ST7565_POWER_CONTROL_SET(0x6));
+ ao_delay(AO_MS_TO_TICKS(50));
+ ao_st7565_instruction(ST7565_POWER_CONTROL_SET(0x7));
+ ao_delay(AO_MS_TO_TICKS(10));
+ ao_st7565_instruction(ST7565_RESISTOR_RATIO_SET(5));
+ ao_st7565_instruction(ST7565_DISPLAY_ON);
+ ao_st7565_set_brightness(13);
+}
+
+static uint8_t rotbuf[AO_ST7565_WIDTH];
+
+#define WIDTH AO_ST7565_WIDTH
+#define HEIGHT AO_ST7565_HEIGHT
+#define STRIDE AO_BITMAP_STRIDE(WIDTH)
+
+static uint32_t previous_image[STRIDE * HEIGHT];
+
+void
+ao_st7565_update(struct ao_bitmap *bitmap)
+{
+ int16_t col, c, page;
+ int16_t row;
+ uint32_t *line, *prev, *l;
+ uint32_t bits;
+ uint8_t *r;
+ int16_t min_col, min_row, max_col, max_row;
+ int16_t min_page, max_page;
+
+ ao_st7565_setup();
+
+ min_col = STRIDE - 1;
+ max_col = 0;
+ min_row = HEIGHT - 1;
+ max_row = 0;
+ line = bitmap->base;
+ prev = previous_image;
+ for (row = 0; row < HEIGHT; row++) {
+ for (col = 0; col < STRIDE; col++) {
+ bits = *line++;
+ if (bits != *prev) {
+ *prev = bits;
+ if (row < min_row)
+ min_row = row;
+ if (row > max_row)
+ max_row = row;
+ if (col < min_col)
+ min_col = col;
+ if (col > max_col)
+ max_col = col;
+ }
+ prev++;
+ }
+ }
+
+ if (min_col > max_col || min_row > max_row)
+ return;
+
+ min_page = min_row >> 3;
+ max_page = max_row >> 3;
+ line = bitmap->base + min_page * 8 * STRIDE + min_col;
+
+ uint8_t first_col = (uint8_t) (min_col * 32);
+ uint8_t num_col = (uint8_t) (max_col + 1 - min_col) * 32;
+
+ for (page = min_page; page <= max_page; page++) {
+ uint8_t i[4] = {
+ ST7565_PAGE_ADDRESS_SET(7-(uint8_t) page),
+ ST7565_COLUMN_ADDRESS_SET_MSN(first_col >> 4),
+ ST7565_COLUMN_ADDRESS_SET_LSN(first_col & 0xf),
+ ST7565_RMW
+ };
+ memset(rotbuf, 0, num_col);
+ for (row = 7; row >= 0; row--) {
+ r = rotbuf;
+ l = line;
+ line += STRIDE;
+ for (col = min_col; col <= max_col; col++) {
+ bits = ~*l++;
+ for (c = 0; c < 32; c++) {
+ *r++ |= ((bits >> c) & 1) << row;
+ }
+ }
+ }
+ ao_st7565_instructions(i, 4);
+ ao_st7565_data(rotbuf, num_col);
+ }
+}
+
+void
+ao_st7565_init(void)
+{
+ memset(previous_image, 0xff, sizeof(previous_image));
+ ao_enable_output(AO_ST7565_RESET_PORT, AO_ST7565_RESET_PIN, 1);
+ ao_enable_output(AO_ST7565_A0_PORT, AO_ST7565_A0_PIN, 1);
+
+ ao_enable_cs(AO_ST7565_CS_PORT, AO_ST7565_CS_PIN);
+}
projects / fw / altos / blobdiff