Hi,

I am trying to build a simple SPI slave communication protocol for an existing master. The master device is an Atmega microcontroller, with an SPI clock approximately 40Kbps.

There are two types of messages: first one is master write messages, and second one is master read messages. And I want to implement all protocol logic in interrupt handler...

The problem is; I cant simply use buffered mode, since master write packets should echo the incoming packet (with one or two bytes exception) immediately.

SCB is configured in SPI slave mode, with 0 software buffer size (RX and TX buffer sizes are 8). Interrupt is configured as Internal, and the only interrupt source selected is "RX FIFO Not Empty".

Code is written with following naming notations...

Every thing starting with cy are cypress conponents, and everything starting with comm are related with my communication routines.

the following code is my custom SPI ISR function.

//WRITE MESSAGE FORMAT:

// <WriteSlaveCommand><TotalSize><PayloadSize><...PAYLOAD...><MasterMagic><CRC>

// Response should be an echo (only change MasterMagic with SlaveMagic, and update CRC accordingly)

//READ MESSAGE FORMAT:

// <WriteSlaveCommand><TotalSize><PayloadSize><...0xFF's...><MasterMagic><CRC>

//Response should be populated accordingly

void _commParsePacket(void)

{

    //store received byte

    _commRxByte = cySPI_RX_FIFO_RD_REG;

    while(0u != cySPI_GET_RX_FIFO_ENTRIES);

    cySPI_ClearRxInterruptSource(cySPI_INTR_RX_NOT_EMPTY);

    //if software buffer enabled

    //cySPI_rxBufferHead = 0;

    //cySPI_rxBufferTail = 0;   

    switch(_parseIndex)

    {

        //wait for Write or Read command

        case 0:

            commRxCrcReset();

            commPacket.command = _commRxByte;

           //Clear/Invalidate TX buffer

            cySPI_TX_FIFO_CTRL_REG |= 0x00010000;

            cySPI_TX_FIFO_CTRL_REG &= 0xFFFEFFFF;

            if ((commPacket.command == WriteSlaveCommand) || (commPacket.command == ReadSlaveCommand))

            {

                commStartedCount++;

                commTxCrcReset();

                _commTxByte = commPacket.command;

                if (commPacket.command == WriteSlaveCommand)

                {

                    commPacket.payload = (unsigned char*)&commMosiPacket; //if command is a write command, fill this structure

                }

                else

                {

                    commPacket.payload = (unsigned char*)&commDummyPacket; //if command is a read command, fill a dummy/temporary structure

                                                                                                                           //note: already populates MisoPacket is going to be transferred

                }

                _parseIndex++;

            }

            commRxCrcUpdate(_commRxByte);

            break;

        // wait for total size

        case 1:

            commPacket.totalSize = _commRxByte;

            _commTxByte = commPacket.totalSize;

            commRxCrcUpdate(commPacket.totalSize);

            _parseIndex++;

            break;

        //wait for payload size           

        case 2:

            commPacket.payloadSize = _commRxByte;

            commRxCrcUpdate(commPacket.payloadSize);

            //check for payload sizes... return to parseIndex=0 to avoid a possible data overflow

            if( ((commPacket.command == ReadSlaveCommand) && (commPacket.payloadSize ==  5)) ||

                ((commPacket.command == WriteSlaveCommand) && (commPacket.payloadSize == 17)) )

            {

                _commTxByte = commPacket.payloadSize;

                _parsePacketIndex = 0;

                _parseIndex++;

            }

            else

            {

                _parseIndex = 0;

            }

            break;

        //fill payloads

        case 3:

            if (_parsePacketIndex < commPacket.payloadSize)

            {

                commPacket.payload[_parsePacketIndex] = _commRxByte;

                if (commPacket.command == ReadSlaveCommand)

                {

                    _commTxByte = ((unsigned char*)(&commMisoPacket))[_parsePacketIndex];

                }

                else

                {

                    _commTxByte = ((unsigned char*)(&commMosiPacket))[_parsePacketIndex];

                }

                commRxCrcUpdate(_commRxByte);           

                _parsePacketIndex++;

            }

            if (_parsePacketIndex == commPacket.payloadSize)

            {

                _parseIndex++;

            }

            break;

        //replace magic numbers

        case 4:

            commPacket.magicNumber = _commRxByte;

            _commTxByte = SlaveMagic;

            commRxCrcUpdate(commPacket.magicNumber);

            _parseIndex++;

            break;

        //wait and check for CRC's

        case 5:

            commPacket.crc = _commRxByte;

            _commTxByte = commTxCrcGet();

            _parseIndex++;

            if (commPacket.crc == commRxCrcGet())

            {

                if (commPacket.command == WriteSlaveCommand)

                    _commSuccess = 0x00;

            }

            break;

        //wait for my CRC to be send...

        default:

            _parseIndex = 0;

            //_commResetTXBuff();

            //return;

            break;

    }  

    //transmit

    cySPI_TX_FIFO_WR_REG = _commTxByte;

    commTxCrcUpdate(_commTxByte);

    //if software buffer enabled

    //cySPI_txBufferHead = 1;

    //cySPI_txBufferTail = 0;

    return;

}

I am using Psoc Creator 4.1, and my device is CY8C4124...

Also note that "Slave Select" is always selected.

Problem is;

1 - It seems nearly 1/2 of the time, they just communicate ok.

2 - If I read failed packets, I see data is late 1 or 2 bytes...

Thanks...

Hi,

Is there any max number of packets that we can send in one connection interval?

Thank You

I'm using an EZ BLE module CYBLE-214009-EVAL with a Pioneer board and trying to use the example program BLE_4.2_DataLength_Security_Privacy.  It complains that I'm trying to use a data length greater than 27 bytes which my device can't handle. I take this to mean that the EZ-BLE module has BLE 4.1 or earlier and so can't deal with BLE 4.2 settings.

Can this device be upgraded to BLE 4.2? 

Would you be kind enough to tell me how to do it?

Thanks,

Dennis

10bit ADC(CSD)は外付けのCapacitorが必要になるのでしょうか？

電気的特性（DC and AC Electrical Characteristics）には、以下のような記載がございます。

Hello,

I am succesfully using a button on P0.7 to generate a wake-up interrupt from stop mode. I have done this the same way as in AN86233.

Is there a way to add a functionality to generate a software reset of the PSoC when in active mode? I would like to reset the PSoC when in active mode and wake up the PSoC when in stop mode.

I tried to add the following line of code into the ISR, but nothing happens.

CY_ISR(WakeUp_Isr)
{
    // clears the interrupt on change flag
    Pin_SW1_ClearInterrupt();
    // TODO - reset doesn't happen
    CySoftwareReset();
}

Thank you,

David

Hi all,

While researching for 5V arm cortex microcontrollers, I found cypress microcontrollers.

The part I have selected is:

CY8C4125AXI-S433

The circuit I am trying to design needs:

5V 300kHz PWM. 20-80% duty cycle.

For analog input, I am planning to use 5V VDDA and 4.096V external reference, to get better immunity to noise.

I just wanted to verify if this is possible with the part mentioned above. Looking at the datasheet it looks like this is possible.

Any suggestions or recommendation?

Also, can this part be programmed using JLink programmer in Keil Uvision?

Thanks.