MSP430 G2553 UART Baudrate 9600 16MHz clock Issues - uart

I'm interfacing my G2553 to a standard LCD screen using UART. I got it working like a dream at 1MHz, but need the system to run at 16MHz for certain other peripherals. I got it very close to working at 16MHz but there is what I believe to be a baudrate error, as the screen will show almost what I sent it, but miss a character here or there or get a character incorrect. I'll take you through how I wrote my code to see if I made any errors.
The screen expects a baudrate of 9600, so I went to the table in my user guide:
So UCBRx = 1666
and UCBRSx = 6.
The expected % errors on this are actually better than what I was using at the 1MHz clock so I thought this would be OK.
This means UCBR0 = 130 and UCBR1 = 6 (This is just the HEX value of UCBRx spread over two 8-bit registers) and UCBRSx = 6.
Now to enter these I looked at what the user guide tells us about the UART modulation register:
(was going to make this pretty but I don't have the reputation to post images)
So my initialisation code ended up being:
if (CALBC1_16MHZ==0xFF) // If calibration constant erased
{
while(1); // do not load, trap CPU!!
}
DCOCTL = 0; // Select lowest DCOx and MODx settings
//setup DCO to 16MHZ
BCSCTL1 = CALBC1_16MHZ;
DCOCTL = CALDCO_16MHZ;
P1SEL |= BIT1 + BIT2 ; // P1.1 = RXD, P1.2=TXD
P1SEL2 |= BIT1 + BIT2;
UCA0CTL1 |= UCSSEL_2; // SMCLK
UCA0BR0 = 130; // 16MHz 9600
UCA0BR1 = 6; // 16MHz 9600
UCA0MCTL = UCBRS2 + UCBRS1; // modulation is 110b or 6
UCA0CTL1 &= ~UCSWRST; // **Initialize USCI state machine**
However as I stated above this is almost there, for example if I try to display the string "Initialising..." which worked for my 1MHz 9600 baudrate settings, with 16MHz at these settings it might display "Initiali ng..." - something close but obviously some error in there that I don't want.
Thank you for any help you can provide on this.

According to the baud rate calculator at http://mspgcc.sourceforge.net/baudrate.html, UCA0MCTL is supposed to be 0x5B

Related

ATMEGA2561 WINC1500 Driver implementation SPI problem

I am trying to implement the WINC1500 MLA Driver to work with the ATMEGA2561 MCU and I have written my driver code and it's stuck on the line "while((SPSR & (1 << SPIF)) == 0);" in the m2mStub_SpiTxRx function.
I have no idea why it's not progressing through. I'm using the jumpstart ImageCraft IDE for this project.
Here's the implementation of it
void m2mStub_SpiTxRx(uint8_t *p_txBuf,
uint16_t txLen,
uint8_t *p_rxBuf,
uint16_t rxLen)
{
uint16_t byteCount;
uint16_t i;
// Calculate the number of clock cycles necessary, this implies a full-duplex SPI.
byteCount = (txLen >= rxLen) ? txLen : rxLen;
DEBUGOUTF("Calculate the number of clock cycles\n");
DEBUGOUTF("byteCount %d", byteCount, "\n");
DEBUGOUTF("txLen %d", txLen, "\n");
DEBUGOUTF("rxLen %d", rxLen, "\n");
// Read / Transmit.
for (i = 0; i < byteCount; ++i)
{
// Wait for transmitter to be ready. (This is causing the entire thing to crash)
while((SPSR & (1 << SPIF)) == 0);
// Transmit.
if (txLen > 0)
{
// Send data from the transmit buffer.
SPDR = (*p_txBuf++);
--txLen;
}
else
{
// No more Tx data to send, just send something to keep clock active.
SPDR = 0x00U;
}
// Wait for transfer to finish.
while((SPSR & (1 << SPIF)) == 0);
// Send dummy data to slave, so we can read something from it.
SPDR = 0x00U;
// Wait for transfer to finish.
while((SPSR & (1 << SPIF)) == 0);
// Read or throw away data from the slave as required.
if (rxLen > 0)
{
*p_rxBuf++ = SPDR;
--rxLen;
}
else
{
// Clear the registers
volatile uint8_t reg_clear = 0U;
reg_clear = SPDR;
(void)reg_clear;
}
}
}
I don't have enough information to say for sure, but my assumption is that your SPI connection is not set up correctly.
In particular, I guess you forgot to set /SS as output, same as this problem or this.
In the datasheet it says:
Master Mode When the SPI is configured as a master (MSTR in SPCR is
set), the user can determine the direction of the SS pin.
If SS is configured as an output, the pin is a general output pin
which does not affect the SPI system. Typically, the pin will be
driving the SS pin of the SPI slave.
If SS is configured as an input, it must be held high to ensure Master
SPI operation. If the SS pin is driven low by peripheral circuitry
when the SPI is configured as a master with the SS pin defined as an
input, the SPI system interprets this as another master selecting the
SPI as a slave and starting to send data to it. To avoid bus
contention, the SPI system takes the following actions:
The MSTR bit in SPCR is cleared and the SPI system becomes a slave. As a result of the SPI becoming a slave, the MOSI and SCK pins become
inputs.
The SPIF flag in SPSR is set, and if the SPI interrupt is enabled, and the I-bit in SREG is set, the interrupt routine will be executed.
Thus, when interrupt-driven SPI transmission is used in master mode,
and there exists a possibility that SS is driven low, the interrupt
should always check that the MSTR bit is still set. If the MSTR bit
has been cleared by a slave select, it must be set by the user to
re-enable SPI master mode.
So, you just need to configure the /SS pin as output and set to high in your init code, this should solve your problem:
DDRB |= (1 << PB0); // Set /SS (PB0) as output
PORTB |= (1 << PB0); // Set /SS (PB0) high

How Can I Establish UART Communication between 2 Stm32 and produce PWM signal

Edit: I solved UART communication problem but I have new problem getting pwm signal after receiving Transmit Data. I can blink led I can drive relay with transmitted data but I could not produce PWM signal.
maps(120, 1, 1, 250, RxData[4]);
ADC_Left = Yx; __HAL_TIM_SET_COMPARE(&htim2,TIM_CHANNEL_1,ADC_Left);
I used __HAL_TIM_SET_COMPARE function but it doesnt work. I can observe ADC_Left’s value on Debug site but its not work.
I am trying to realize UART communication between 2 stm32. I know there are several topic related with but my question focused another one.
I am reading 2 adc value on stm32 which is only transmit these value and other one only receive these 2 adc value. To do this
MX_USART1_UART_Init();
__HAL_UART_ENABLE_IT(&huart1, UART_IT_RXNE); // Interrupt Enable
__HAL_UART_ENABLE_IT(&huart1, UART_IT_TC);
char TxData1[10];
..............
TxData1[0] = 0xEA;
TxData1[1] = wData.Byte_1;
TxData1[2] = wData.Byte_2;
TxData1[3] = wData.Byte_3;
TxData1[4] = wData.Right_Adc_Val;
TxData1[5] = wData.Left_Adc_Val;
TxData1[6] = wData.Byte_6;
for(uint8_t i = 1 ; i < 7; i++)
{
wData.Checksum = wData.Checksum + TxData1[i];
}
wData.Checksum_H = (wData.Checksum >> 8)&0xFF;
wData.Checksum_L = (wData.Checksum)&0xFF;
TxData1[7] = wData.Checksum_H;
TxData1[8] = wData.Checksum_L;
TxData1[9] = 0xAE;
HAL_UART_Transmit_IT(&huart1,(uint8_t*) &TxData1,10);
............
This block sent them I can observate them on Debug screen and using TTL module's Tx Rx pins.
MX_USART1_UART_Init();
__HAL_UART_ENABLE_IT(&huart1, UART_IT_RXNE); // Interrupt Enable
__HAL_UART_ENABLE_IT(&huart1, UART_IT_TC);
char RxData[10];
while(1){
HAL_UART_Receive_IT(&huart1,(uint8_t*) &RxData,10);
}
void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)
{
if(huart->Instance == USART1)
{
HAL_UART_Receive_IT(&huart1,(uint8_t*) &RxData,10);
}
There is no problem up to here but when i getting RxData 0. index , it gives EA . Of course it should be give EA. When the adc data change all the ranking is changing. RxData[0] gives meaningless data. adc value is jumping over the all RxData array.
data locations must always be in the same index. How Can I get these data in stability for ex.
RxData[0]=EA
.
.
RxData[4]= should give adc value. so on.
..
Edit: I tried other mode of UART, DMA (in circular mode) and direct mode were used. I cant receive even 1 byte with DMA .
In your example code, you have an extra & that needs to be removed from both the transmit and receive HAL method calls. Example:
HAL_UART_Transmit_IT(&huart1,(uint8_t*) &TxData1,10);
HAL_UART_Transmit_IT(&huart1,(uint8_t*) TxData1,10);
To avoid this type of error in the future, recommend not using the cast and try something like the following:
uint8_t TxData1[10];
...
HAL_UART_Transmit_IT(&huart1, TxData1, sizeof(TxData1);

Attiny204 Interrupt Flag Not Being Generated

I'm trying to write a (fairly) basic bit of software for and Attiny204, which handles interrupts when a clock input is pulled high.
When I run the code in the debug simulator in Atmel Studio, and set the clock input high, there is no interrupt flag generated. The interrupts do trigger when I manually produce an interrupt flag.
I've tried using different pins, and even, the other port. I can't seem to get the simulator to produce the interrupt flag.
In the past, I have used the AtMega328P in the simulator with equivalent code, and it works fine.
ISR(PORTA_PORT_vect)
{
//In this function we must:
//1. Shift all data up
shiftUp();
//2. Get new 8th bit
bit8 = VPORTA.IN & (1 << 1);
//3. Set Data Output Pin to bit0
if(bit0 == 0)
VPORTA.OUT &= ~(1 << 3);
else
VPORTA.OUT |= (1 << 3);
//4. Calculate new dimValue and dimMilliseconds
calcDim();
calcDelay();
}
int main(void)
{
initVariables();
/*
Below this, we must set the Data Direction (DD) of each pin we assigned.
*/
//Below, set the ISC of the Zero Cross Pin and the Clock Pin to allow interrupts
PORTA_PIN0CTRL |= 0b00000001; //Zero Cross
//PORTA_PIN1CTRL = 0b00000000; //Data In
//PORTA_PIN2CTRL = 0b00000000; //Data Next
//PORTA_PIN3CTRL = 0b00000000; //Triac Control
PORTB_PIN0CTRL |= 0b00000001; //Clock
//VPORTB.INTFLAGS |= 0b00000001;
//Set Port direction.
VPORTA.DIR = 0x30;
VPORTB.DIR = 0x00;
/*
Below this, we must enable interrupts.
*/
sei();
/* Replace with your application code */
while (1)
{
}
}
Why are you writing to VPORTA and VPORTB? The Tiny204 doesn´t have this registers.
You enable interrupts on both edges for Pin 0 of Port A (PIN0CTRL bit 0 is set = BOTHEDGES) and you don´t clear the interrupt flag in your ISR of Port A. Please take a look at the data sheet:
The interrupt request remains active until the interrupt flag is cleared. See the peripheral's INTFLAGSregister for details on how to clear interrupt flags.

Why HM-10 doesn't send an OK if i send AT from an MSP430 Launchpad?

I'm trying to set up an UART communication with a HM-10 chip on a Texas Instruments MSP430 Launchpad, but I ran into a very elementary problem.
What I want to achieve is to send an "AT" through UART to HM-10, and receive an answer for that. By the way this is a code I found here and I slightly modified for my purposes.
#include "msp430g2553.h"
const char string[] = { "AT" };
unsigned int i;
void main(void)
{
WDTCTL = WDTPW + WDTHOLD; // Stop the Watch dog
//------------------- Configure the Clocks -------------------//
if (CALBC1_1MHZ==0xFF) // If calibration constant erased
{
while(1); // do not load, trap CPU!!
}
DCOCTL = 0; // Select lowest DCOx and MODx settings
BCSCTL1 = CALBC1_1MHZ; // Set range
DCOCTL = CALDCO_1MHZ; // Set DCO step + modulation
//---------------- Configuring the LED's ----------------------//
P1DIR |= BIT0 + BIT6; // P1.0 and P1.6 output
P1OUT &= ~BIT0 + BIT6; // P1.0 and P1.6 = 0
//--------- Setting the UART function for P1.1 & P1.2 --------//
P1SEL |= BIT1 + BIT2; // P1.1 UCA0RXD input
P1SEL2 |= BIT1 + BIT2; // P1.2 UCA0TXD output
//------------ Configuring the UART(USCI_A0) ----------------//
UCA0CTL1 |= UCSSEL_2 + UCSWRST; // USCI Clock = SMCLK,USCI_A0 disabled
UCA0BR0 = 104; // 104 From datasheet table-
UCA0BR1 = 0; // -selects baudrate =9600,clk = SMCLK
UCA0MCTL = UCBRS_1; // Modulation value = 1 from datasheet
//UCA0STAT |= UCLISTEN; // loop back mode enabled
UCA0CTL1 &= ~UCSWRST; // Clear UCSWRST to enable USCI_A0
//---------------- Enabling the interrupts ------------------//
IE2 |= UCA0TXIE; // Enable the Transmit interrupt
IE2 |= UCA0RXIE; // Enable the Receive interrupt
_BIS_SR(GIE); // Enable the global interrupt
i = 0;
UCA0TXBUF = string[i]; // Transmit a byte
_BIS_SR(LPM0_bits + GIE); // Going to LPM0
}
//-----------------------------------------------------------------------//
// Transmit and Receive interrupts //
//-----------------------------------------------------------------------//
#pragma vector = USCIAB0TX_VECTOR
__interrupt void TransmitInterrupt(void)
{
P1OUT ^= BIT0;//light up P1.0 Led on Tx
if (i == sizeof string - 1)
{
UC0IE &= ~UCA0TXIE;
}
UCA0TXBUF = string[i++];
}
#pragma vector = USCIAB0RX_VECTOR
__interrupt void ReceiveInterrupt(void)
{
// light up P1.6 LED on RX
if (UCA0RXBUF == 'O')
{
P1OUT ^= BIT6;
}
IFG2 &= ~UCA0RXIFG; // Clear RX flag
}
According to the datasheet I should receive an OK answer for this command.
If there was an 'O' in the RX buffer, I would expect the LED to light up on my board, but that doesn't happen.
Using Code Composer, I also verified with adding a breakpoint to the RX interrupt that there is indeed no RX answer.
I believe this is entirely a software question, that's why I put it here. I'm using the correct rotation of jumpers(http://xanthium.in/Serial-Communication-MSP430-UART-USCI_A) and RX is wired to TX and vica versa.
I would appreciate if you could point out if I was doing anything conceptionally wrong or if I just made a mistake. Thank you!
I see a problem in the interrupt routine TransmitInterrupt(): you should use UCA0TXBUF = string[++i]; because using "i++" you transmit two times the letter "A". The test about sizeof(string) should also be retouched.
Then, I would not trust too much the datasheet. I think that, despite what the datasheet says, every command sent to the modem must be terminated by CR (\r), otherwise how could the modem discern an "AT" from an "AT+RESET"? I am not really sure but the datasheet doesn't seem a high quality one. Anyway, it's a quick test (to add a \r to the end of the string).
Finally, the CTS and RTS signals can play a role too. Some modem wants RTS asserted, other modems don't care, and terminology sometimes is confusing: when datasheet says RTS, does it mean RTS of the modem or RTS of the host? I hope this helps, you should do a few scientific tries.
I think for everyone who is working with HM-10 devices in the future I want to answer this question, because it has I think its own sort of mini-literature, which was first frustrating, but then I kind of liked the challenges it posed to me.
Some of the problems are hardware related, so this post might need to be moved to an embedded engineering section. (Great consequence - you cannot be 100% sure before checking it with a scope)
Know your hardware - HM-10 has tons of versions, and it turned our one needed an extra potential divider because it has a 3.3V logic level high instead of 5V. This website is a fantastic place to start. Though, ours turned out to be an MLT-BT05 which is a clone of a clone. It doesn't have iBeacon capability on its firmware, so if you don't want to power cycling, then you should probably avoid this one.
About the coding bit the most important thing is to check with \n, \r and \n\r, as linuxfan briefly mentioned its importance above, because some of the devices need it. The best place to start is AT and if it works, then use AT+HELP and find the version, usually AT+VERSION command so you can identify with 100% certainty which chip you have.
Currenetly it is prototyped on an Arduino, but I will include working code as soon as its finished on MSP430.
The Arduino code:
#include <SoftwareSerial.h>
SoftwareSerial bluetooth(9, 10); // RX, TX
char commandbuffer[50];
int j = 0;
void setup()
{
memset(commandbuffer, 0, sizeof(commandbuffer));
analogWrite(12, 255);
analogWrite(11, 0);
// Start the hardware serial port
Serial.begin(19200);
bluetooth.begin(9600);
// un REM this to set up a Master and connect to a Slave
Serial.println("BLE CC41A Bluetooth");
Serial.println("----------------------------------");
Serial.println("");
Serial.println("Trying to connect to Slave Bluetooth");
delay(1000);
bluetooth.println("AT"); // just a check
delay(2000);
bluetooth.println("AT+NAMEHIST");
delay(2000);
bluetooth.println("AT+ROLE0");
delay(2000);
bluetooth.println("AT+INQ"); // look for nearby Slave
delay(5000);
bluetooth.println("AT+CONN1"); // connect to it */
}
void loop()
{
bluetooth.listen();
// while there is data coming in, read it
// and send to the hardware serial port:
while (bluetooth.available() > 0) {
char inByte = bluetooth.read();
Serial.write(inByte);
}
// Read user input if available.
if (Serial.available()) {
delay(10); // The DELAY!
char temp = Serial.read();
if (temp == '\n')
{
bluetooth.println(commandbuffer);
Serial.println(commandbuffer);
memset(commandbuffer, 0, sizeof(commandbuffer));
j = 0; // Reset
}
else
{
commandbuffer[j++] = temp;
}
delay(500);
}

PIC Capture mode not triggering interrupt

I'm trying to use the capture module on a PIC 16LF1827, but the ISR is never entered. I started with a basic falling-edge interrupt (worked), then added in the timer 1 configuration (still working), then disabled the IOC interrupt and configured/enabled the relevant CCP interrupt (ISR is never entered). The code is below: the commented section is the original basic IOC setup.
I've verified with the MPLab debugger that the ISR is not entered, and confirmed this by hooking it up to a logic analyzer and watching RB1.
#include "htc.h"
//config1
//internal osc, no wdt, use power-up timer, enable reset
// no code protection, brown-out-reset enabled, clkout is gpio,
// internal-external switchover off, failsafe clock monitor off
__CONFIG(FOSC_INTOSC & WDTE_OFF & PWRTE_ON
& MCLRE_ON & CP_OFF & CPD_OFF & BOREN_ON
& CLKOUTEN_OFF & IESO_OFF & FCMEN_OFF);
//config2 (following MPLab's complaints when running debugger)
//low-voltage programming off, debug on, brown-out reset at 2.7 v
// stack over/under flow triggers reset, no 4x pll,
// no flash write protection
__CONFIG(LVP_OFF & DEBUG_ON & BORV_27
& STVREN_ON & PLLEN_OFF & WRT_OFF);
void interrupt isr(void){
//bounce pin 1
LATB ^= 0b10;
LATB ^= 0b10;
if(IOCIF && IOCBF0){
IOCBF0 = 0;
IOCIF = 0;
}
if (CCP1IF){
CCP1IF = 0;
}
}
void main(void){
//configure internal oscillator:
//PLL = 0, source = from config 1, frequency = 4 mhz
//0b0: SPLLEN_OFF
OSCCONbits.SPLLEN = 0b0;
//0b00: use config word 1
OSCCONbits.SCS = 0b00;
//0b1101: 4 mhz frequency
OSCCONbits.IRCF = 0b1101;
//configure peripherals
//PORT A: LEDs (output), digital
TRISA = 0x00;
ANSELA = 0;
//PORT B: digital, 0 = input, 1 = output, rest don't care
TRISB = 0b11111101;
ANSELB = 0;
//configure timer 1 (not needed for basic IOC)
//source = instruction clock, prescale = 1:1, disable LP osc, do synchronize (DC)
//0b00: instruction clock
T1CONbits.TMR1CS = 0b00;
//0b00: 1:1
T1CONbits.T1CKPS = 0b00;
//0b0: lp osc off
T1OSCEN = 0b0;
//0b0: synch (ignored)
nT1SYNC = 0b0;
//interrupts
/*
//IOC enabled on falling edge for port B 0
IOCBN0 = 0b00000001;
IOCIE = 1;
*/
//Capture on falling edge for port B 0
//notes in 23.1 of DS: disable interrupt, set operating mode, clear flag, enable interrupt
CCP1IE = 0b0;
//0b100: every falling edge
CCP1CONbits.CCP1M = 0b100;
CCP1IF = 0b0;
CCP1IE = 0b1;
//enable peripheral interrupts, global interrupts
PEIE = 1;
GIE = 1;
//start timer 1
TMR1ON = 1;
while(1){
//Toggle led 0
LATA ^= 0b1;
}
}
I'm using the HI-TECH C compiler (lite), running in MPLab.
Any suggestions would be greatly appreciated. My apologies if I butcher terminology, this is my first project on a PIC.
Your setting for TRISB1 is as an output. According to the datasheet, the capture pin needs to be configured as an input. For the GPIO pins, setting the TRIS bit a 0 is an output, 1 is for an input.
EDIT: Forgive the initial stupid answer as I didn't realize you were using PORTB1 as a GPIO indicator for your scope.
So initially you used PORTB0 as your capture pin correct (using IOC)? The capture module uses a different GPIO port for its input (PORTB3 for CCP1). Did you move the connection to PORTB3 for your capture source?
EDIT: After some more looking through the PIC datasheet I noticed that CCP1's GPIO pin can be moved from PORTB3 to PORTB0 but I don't see any reference to how you set the APFCON0.CCP1SEL bit. That would be something else to check.