Trying EFM8UB10 platform and making a current sensor with oled screen. Both I2C. When uploading data array to display. It seems to send random bytes (sometimes sending bytes from previous function) and makes main loop. On analyzer it shows random bytes and repeats. What an cause this issue?
Main has just display();
]
SendByte:
Smbus interrupt send:
Attaching analyzer reading. You can see its sending proper bytes to config the screen but then it sends all kinds of bytes and loops.
Main has just display();
Code:
void display(void)
{
uint16_t i;
I2C_MasterWrite(OledDisp); // sets position on lcd
for (i = 0; i < 512; i++) {
SSDData(0x40); //data
SSDData(0x00); // 0 clear
}
}SendByte:
Code:
void SSDData(uint8_t c)
{
TARGET = 0x3C; //Slave Address
SMB_DATA_OUT[0] = c;// Load first data byte
NUM_BYTES_WR = 1; // Number of bytes to transmit
while(SMB_BUSY); // Wait for SMBus to be free.
SMB_BUSY = 1; // Claim SMBus (set to busy)
SMB_RW = 0; // Write
SMB0CN0_STA = 1; //initiate the transaction by setting the start-condition bit
SFRPAGE = SMB0_PAGE;
while(SMB_BUSY);
}
Code:
SI_INTERRUPT(SMBUS0_ISR, SMBUS0_IRQn)
{
bool FAIL = 0; // Used by the ISR to flag failed
// transfers
static uint8_t sent_byte_counter;
static uint8_t rec_byte_counter;
if (SMB0CN0_ARBLOST == 0) // Check for errors
{
// Normal operation
switch (SMB0CN0 & 0xF0) // Status vector
{
// Master Transmitter/Receiver: START condition transmitted.
case SMB_MTSTA:
SMB0CN0_STA = 0; // Manually clear START bit
SMB0CN0_STO = 0; // Manually clear STOP bit
SMB0DAT = (TARGET<<1)|SMB_RW; // Load R/W bit
SMB0CN0_SI = 0; // Clear interrupt flag
sent_byte_counter = 0; // Reset W byte counter
rec_byte_counter = 1; // Reset R byte counter
break;
// Master Transmitter: Data byte transmitted
case SMB_MTDB:
if (SMB0CN0_ACK) // Slave SMB0CN0_ACK? After Address
{
if (SMB_RW == WRITE) // If this transfer is a WRITE,
{
if (sent_byte_counter == NUM_BYTES_WR) // If byte count from array
{
SMB0CN0_STO = 1; //transmit stop condition
SMB_BUSY = 0; // And free SMBus
SMB0CN0_SI = 0; // Clear interrupt flag
}
else
{
SMB_DATA_OUT++; //increment pointer that points at data to be transmitted
SMB0DAT = *SMB_DATA_OUT; //write next byte to SMBus data register
sent_byte_counter++;
}
}
else {} // If this transfer is a READ,
// proceed with transfer without
// writing to SMB0DAT (switch
// to receive mode)
}
else // If slave NACK,
{
SMB0CN0_STO = 1; // Send STOP condition, followed
SMB0CN0_STA = 1; // By a START
// Indicate error
}
break;
}
