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October 18, 2022 03:19
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| /* | |
| * Below is a a modified version of the TI MSP430 LCDE_01 example named `msp430fr413x_LCDE_01.c` | |
| * It simply displays the numbers 1-6 on the built-in LCD display on the MSP-EXP430FR4133 Lanuchpad. | |
| * | |
| * I could not find any ultra-low power examples of an MSP430 driving and LCD, so I started with | |
| * the TI code and kept updating it to try to use less power using things I noticed in the datasheets. | |
| * | |
| * I was able to drop the current usage from 200uA down to less than 1uA without any noticable change in functionality. | |
| * | |
| * I hope to write a full article about this and other MSP430 power optimization techniques on josh.com soon. | |
| * | |
| * Modifications (c)2022 Josh Levine | |
| */ | |
| // Progress: | |
| // 200uA - Initial | |
| // 4.2uA - All GPIO to output low | |
| // 2.9uA - Disable charge pump, Vlcd = Vcc | |
| // 2.7uA - Switch LCD clock from XTAL to VLO | |
| // 1.8uA - Switch LCD to low power waveform | |
| // 1.0uA - Div LCD clock by 4 | |
| // 0.9uA - Disable SVS | |
| /* --COPYRIGHT--,BSD_EX | |
| * Copyright (c) 2014, Texas Instruments Incorporated | |
| * All rights reserved. | |
| * | |
| * Redistribution and use in source and binary forms, with or without | |
| * modification, are permitted provided that the following conditions | |
| * are met: | |
| * | |
| * * Redistributions of source code must retain the above copyright | |
| * notice, this list of conditions and the following disclaimer. | |
| * | |
| * * Redistributions in binary form must reproduce the above copyright | |
| * notice, this list of conditions and the following disclaimer in the | |
| * documentation and/or other materials provided with the distribution. | |
| * | |
| * * Neither the name of Texas Instruments Incorporated nor the names of | |
| * its contributors may be used to endorse or promote products derived | |
| * from this software without specific prior written permission. | |
| * | |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" | |
| * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, | |
| * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR | |
| * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR | |
| * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, | |
| * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, | |
| * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; | |
| * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, | |
| * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR | |
| * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, | |
| * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
| * | |
| ******************************************************************************* | |
| * | |
| * MSP430 CODE EXAMPLE DISCLAIMER | |
| * | |
| * MSP430 code examples are self-contained low-level programs that typically | |
| * demonstrate a single peripheral function or device feature in a highly | |
| * concise manner. For this the code may rely on the device's power-on default | |
| * register values and settings such as the clock configuration and care must | |
| * be taken when combining code from several examples to avoid potential side | |
| * effects. Also see www.ti.com/grace for a GUI- and www.ti.com/msp430ware | |
| * for an API functional library-approach to peripheral configuration. | |
| * | |
| * --/COPYRIGHT--*/ | |
| //****************************************************************************** | |
| // MSP430FR413x Demo - LCD_E, Display a string "123456" on LCD in LPM3.5 mode. | |
| // | |
| // Description: Displays "123456" in sequence to the LCD display. | |
| // f(LCD) = 32768Hz/((7+1)*16) = 256Hz. | |
| // MSP430 works in LPM3.5 mode for ultra low power. | |
| // ACLK = default REFO ~32768Hz, | |
| // MCLK = SMCLK = default DCODIV ~1MHz. | |
| // | |
| // MSP430FR4133 | |
| // ----------------- | |
| // /|\| | | |
| // | | XIN|-- | |
| // GND --|RST | ~32768Hz | |
| // | | XOUT|-- | |
| // |--0.1uF--|R13 | | |
| // |--0.1uF--|R23 (L3)COM3|----------------| | |
| // |--0.1uF--|R33 (L2)COM2|---------------|| | |
| // --|LCDC2 (L1)COM1|--------------||| | |
| // 4.7uF | (L0)COM0|-------------|||| | |
| // --|LCDC1 | ------------- | |
| // | L4~L39|---| 1 2 3 4 5 6 | | |
| // | except L27~L35| ------------- | |
| // | | TI LCD | |
| // | | | |
| // | |
| // LCD pin - Port Pin Map | |
| // LCD pin G6021_LineX | |
| // 1 L8 (P3.0) | |
| // 2 L9 (P3.1) | |
| // 3 L10 (P3.2) | |
| // 4 L11 (P3.3) | |
| // 5 L12 (P3.4) | |
| // 6 L13 (P3.5) | |
| // 7 L14 (P3.6) | |
| // 8 L15 (P3.7) | |
| // 9 L16 (P6.0) | |
| // 10 L17 (P6.1) | |
| // 11 L18 (P6.2) | |
| // 12 L19 (P6.3) | |
| // 13 L20 (P6.4) | |
| // 14 L21 (P6.5) | |
| // 15 L22 (P6.6) | |
| // 16 L23 (P6.7) | |
| // 17 L4 (P7.4) | |
| // 18 L5 (P7.5) | |
| // 19 L6 (P7.6) | |
| // 20 L7 (P7.7) | |
| // 21 L3 (P7.3) | |
| // 22 L2 (P7.2) | |
| // 23 L1 (P7.1) | |
| // 24 L0 (P7.0) | |
| // 25 - | |
| // 26 - | |
| // 27 - | |
| // 28 - | |
| // 29 - | |
| // 30 - | |
| // 31 - | |
| // 32 L24 (P2.0) | |
| // 33 L25 (P2.1) | |
| // 34 L26 (P2.2) | |
| // 35 L36 (P5.4) | |
| // 36 L37 (P5.5) | |
| // 37 L38 (P5.6) | |
| // 38 L39 (P5.7) | |
| // | |
| // Cen Fang | |
| // Wei Zhao | |
| // Texas Instruments Inc. | |
| // Oct 2013 | |
| // Built with IAR Embedded Workbench v5.60 & Code Composer Studio v5.5 | |
| //****************************************************************************** | |
| #include <msp430.h> | |
| #define pos1 4 // Digit A1 - L4 | |
| #define pos2 6 // Digit A2 - L6 | |
| #define pos3 8 // Digit A3 - L8 | |
| #define pos4 10 // Digit A4 - L10 | |
| #define pos5 2 // Digit A5 - L2 | |
| #define pos6 18 // Digit A6 - L18 | |
| const char digit[10] = | |
| { | |
| 0xFC, // "0" | |
| 0x60, // "1" | |
| 0xDB, // "2" | |
| 0xF3, // "3" | |
| 0x67, // "4" | |
| 0xB7, // "5" | |
| 0xBF, // "6" | |
| 0xE4, // "7" | |
| 0xFF, // "8" | |
| 0xF7 // "9" | |
| }; | |
| int main( void ) | |
| { | |
| WDTCTL = WDTPW | WDTHOLD; // Stop watchdog timer | |
| /* | |
| // Configure XT1 oscillator | |
| P4SEL0 |= BIT1 | BIT2; // P4.2~P4.1: crystal pins | |
| do | |
| { | |
| CSCTL7 &= ~(XT1OFFG | DCOFFG); // Clear XT1 and DCO fault flag | |
| SFRIFG1 &= ~OFIFG; | |
| }while (SFRIFG1 & OFIFG); // Test oscillator fault flag | |
| CSCTL6 = (CSCTL6 & ~(XT1DRIVE_3)) | XT1DRIVE_2; // Higher drive strength and current consumption for XT1 oscillator | |
| */ | |
| // Disable the GPIO power-on default high-impedance mode | |
| // to activate previously configured port settings | |
| // Port Configuration all un-used pins to output low | |
| P1OUT = 0x00; | |
| P2OUT = 0x00; | |
| P3OUT = 0x00; | |
| P4OUT = 0x00; | |
| P5OUT = 0x00; | |
| P6OUT = 0x00; | |
| P7OUT = 0x00; | |
| P8OUT = 0x00; | |
| P1DIR = 0xff; | |
| P2DIR = 0xff; | |
| P3DIR = 0xff; | |
| P4DIR = 0xff; | |
| P5DIR = 0xff; | |
| P6DIR = 0xff; | |
| P7DIR = 0xff; | |
| P8DIR = 0x0f; | |
| PM5CTL0 &= ~LOCKLPM5; | |
| // Configure LCD pins | |
| SYSCFG2 |= LCDPCTL; // R13/R23/R33/LCDCAP0/LCDCAP1 pins selected | |
| LCDPCTL0 = 0xFFFF; | |
| LCDPCTL1 = 0x07FF; | |
| LCDPCTL2 = 0x00F0; // L0~L26 & L36~L39 pins selected | |
| //LCDCTL0 = LCDSSEL_0 | LCDDIV_7; // flcd ref freq is xtclk | |
| LCDCTL0 = LCDSSEL__VLOCLK | LCDDIV__4 | LCD4MUX | LCDLP ; // LCD using VLO clock, divide by 4 (on 10KHz from VLO) , 4-mux, low power waveform | |
| // Note that LP lets you pick an even lower clock without noticable flicker! | |
| // LCD Operation - Mode 3, internal 3.08v, charge pump 256Hz | |
| // LCDVCTL = LCDCPEN | LCDREFEN | VLCD_6 | (LCDCPFSEL0 | LCDCPFSEL1 | LCDCPFSEL2 | LCDCPFSEL3); | |
| // LCD Operation - Vlcd=Vcc , charge pump 256Hz | |
| LCDVCTL = LCDCPEN | LCDSELVDD | (LCDCPFSEL0 | LCDCPFSEL1 | LCDCPFSEL2 | LCDCPFSEL3); | |
| LCDMEMCTL |= LCDCLRM; // Clear LCD memory | |
| LCDCSSEL0 = 0x000F; // Configure COMs and SEGs | |
| LCDCSSEL1 = 0x0000; // L0, L1, L2, L3: COM pins | |
| LCDCSSEL2 = 0x0000; | |
| LCDM0 = 0x21; // L0 = COM0, L1 = COM1 | |
| LCDM1 = 0x84; // L2 = COM2, L3 = COM3 | |
| // Display "123456" | |
| LCDMEM[pos1] = digit[1]; | |
| LCDMEM[pos2] = digit[2]; | |
| LCDMEM[pos3] = digit[3]; | |
| LCDMEM[pos4] = digit[4]; | |
| LCDMEM[pos5] = digit[5]; | |
| LCDMEM[pos6] = digit[6]; | |
| LCDCTL0 |= LCDON; // Turn on LCD | |
| /* | |
| In the manual control mode (the LPM5SM bit is set), the LPM3.5 switch is specified by the LPM5SW bit in | |
| the PM5CTL0 register. When LPM5SW is set, the LPM3.5 switch is connected. When LPM5SW is clear, | |
| the LPM3.5 switch is disconnected. It is recommended to turn off the switch to avoid unnecessary leakage | |
| before the device enters LPM3.5. When the device recovers back from LPM3.5 mode, the switch should | |
| be turned on to offer sufficient current for high-frequency operation. | |
| */ | |
| // No effect turning the switch off | |
| //PM5CTL0 = LPM5SM; // The LPM3.5 switch manual mode and off - all peripherals within this domain can accept clock operation no faster than 40 kHz. | |
| PMMCTL0_H = PMMPW_H; // Open PMM Registers for write | |
| //PMMCTL0_L |= PMMREGOFF_L; // and set PMMREGOFF | |
| PMMCTL0_L = PMMREGOFF_L ; // and set PMMREGOFF & disable SVS (on by default, so here we set to 0) | |
| __bis_SR_register(LPM3_bits | GIE); // Enter LPM3.5 | |
| // No effect going into LMP4.5 maybe since all oscs are already off | |
| //__bis_SR_register(LPM4_bits | GIE); // Enter LPM4.5 | |
| __no_operation(); // For debugger | |
| } | |
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