/**************************************************************************** * boards/renesas/m16c/skp16c26/src/m16c_lcd.c * * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. The * ASF licenses this file to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance with the * License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the * License for the specific language governing permissions and limitations * under the License. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include "renesas_internal.h" #include "chip.h" #ifdef CONFIG_SLCD /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /* LCD dimensions ***********************************************************/ #define LCD_NLINES 2 /* Two lines */ #define LCD_NCHARS 8 /* Eight characters per line */ /* LCD commands *************************************************************/ #define LCD_CLEAR 0x01 /* Clear LCD display and home cursor */ #define CURSOR_MODE_DEC 0x04 /* Cursor auto decrement after R/W */ #define CURSOR_MODE_INC 0x06 /* Cursor auto increment after R/W */ #define LCD_CURSOR_ON 0x0e /* Display ON with Cursor */ #define LCD_CURSOR_OFF 0x0c /* Display ON with Cursor off */ #define LCD_CURSOR_BLINK 0x0d /* Display on with blinking cursor */ #define LCD_CURSOR_LEFT 0x10 /* Move Cursor Left One Position */ #define LCD_CURSOR_RIGHT 0x14 /* Move Cursor Right One Position */ #define FUNCTION_SET 0x28 /* Setup, 4 bits,2 lines, 5X7 */ #define LCD_CGRAM 0x40 /* Map characters to CG RAM */ #define LCD_POS_L1(p) (0x80 | p) /* Move cursor to line 1, character p+1 */ #define LCD_POS_L2(p) (0xc0 | p) /* Move cursor to line 2, character p+1 */ #define LCD_HOME_L1 0x80 /* Move cursor to line 1 */ #define LCD_HOME_L2 0xc0 /* Move cursor to line 2 */ /**************************************************************************** * Private Data ****************************************************************************/ static uint8_t g_nchars; /* Number of characters in lines 2 */ static uint8_t g_line[LCD_NCHARS]; /* The content of lines 2 */ /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: up_lcddelay ****************************************************************************/ static void up_lcddelay(uint16_t count) { uint32_t counter = (uint16_t)count << 8; while (counter--) { asm("\tnop\n\tnop\n\tnop\n" : :); /* 3 NOPs */ } } /**************************************************************************** * Name: up_setrs ****************************************************************************/ static inline void up_setrs(bool data) { /* Set/clear bit 1 of port 6 */ register uint8_t regval = getreg8(M16C_P6); if (data) { regval |= (1 << 0); /* High = data */ } else { regval &= ~(1 << 0); /* Low = control */ } putreg8(regval, M16C_P6); } /**************************************************************************** * Name: up_seten ****************************************************************************/ static inline void up_seten(void) { /* Set bit 1 of port 6 */ register uint8_t regval = getreg8(M16C_P6); regval |= (1 << 1); putreg8(regval, M16C_P6); } /**************************************************************************** * Name: up_clren ****************************************************************************/ static inline void up_clren(void) { /* Clear bit 1 of port 6 */ register uint8_t regval = getreg8(M16C_P6); regval &= ~(1 << 1); putreg8(regval, M16C_P6); } /**************************************************************************** * Name: up_enpluse ****************************************************************************/ static inline void up_enpulse(bool data) { up_seten(); /* EN enable chip (HIGH) */ up_lcddelay(0); /* Short delay */ up_clren(); /* Latch data by setting EN low */ up_lcddelay(0); /* Short delay for data writes */ if (!data) up_lcddelay(0); /* Longer delay for control writes */ } /**************************************************************************** * Name: up_lcdwrite ****************************************************************************/ void up_lcdwrite(bool data, uint8_t ch) { up_setrs(data); /* Set RS appropriately */ /* Write upper nibble first. Only the lower 4 bits of P9 are valid. * The upper four bits are reserved and must be zero. */ putreg8(ch >> 4, M16C_P9); up_enpulse(data); /* Write lower nibble second */ putreg8(ch & 0x0f, M16C_P9); up_enpulse(data); } /**************************************************************************** * Name: up_scroll ****************************************************************************/ static void up_scroll(void) { int i; /* Clear the display and position the cursor at the beginning of line 1 */ up_lcdwrite(false, LCD_CLEAR); up_lcdwrite(false, LCD_HOME_L1); /* Copy line 2 to line 1 */ for (i = 0; i < g_nchars; i++) { up_lcdwrite(true, g_line[i]); } /* Position the cursor at the beginning of line 2 */ up_lcdwrite(false, LCD_HOME_L2); g_nchars = 0; } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: up_lcdinit ****************************************************************************/ void up_lcdinit(void) { uint8_t regval; /* Enable writing to PD9 by selecting bit 2 in the protection register */ regval = getreg8(M16C_PRCR); regval |= (1 << 2); putreg8(regval, M16C_PRCR); /* We can't read PD9, so we can't OR the values in */ putreg8(0x0f, M16C_PD9); /* Set EN (port 6 bit 1) and Set RS (port 6 bit 0) as outputs */ regval = getreg8(M16C_P6); regval |= (1 << 1) | (1 << 0); putreg8(regval, M16C_P6); regval = getreg8(M16C_PD6); regval |= (1 << 1) | (1 << 0); putreg8(regval, M16C_PD6); /* Set EN low */ up_clren(); /* Write the reset sequence */ up_lcdwrite(false, 0x33); up_lcddelay(20); up_lcdwrite(false, 0x32); up_lcddelay(20); up_lcdwrite(false, FUNCTION_SET); /* reset sequence */ up_lcdwrite(false, FUNCTION_SET); up_lcdwrite(false, LCD_CURSOR_OFF); up_lcdwrite(false, LCD_CLEAR); up_lcdwrite(false, LCD_HOME_L1); } /**************************************************************************** * Name: up_lcdputc ****************************************************************************/ void up_lcdputc(char ch) { /* Check for new line */ if (ch == '\n') { up_scroll(); } /* Should we wrap to truncate at the end of line??? Let's truncate. * In either case, let's ignore all other non-printable characters. */ else if (g_nchars < LCD_NCHARS && isprint(ch)) { up_lcdwrite(true, ch); g_line[g_nchars] = ch; g_nchars++; } } #endif /* CONFIG_SLCD */