I2C通信用にUM232Hモジュール（FTDI）を構成する際に問題が発生しました。彼らはFTDIのウェブサイトにいくつかの例を掲載しましたが、すべての例が私にはうまくいきません。何が悪いのかわかりません。UM232HをPCF8574Pと通信させたい。PCF8574Pのピンに、点滅したいLEDがあります。これが私が得たセットアップです。ftd2xx.hのヘッダーを使用していますが、それでも彼がftStatusコマンドなどを使用できないというエラーが発生しました。
/******************************************************************************/
/* Include files */
/******************************************************************************/
/* Standard C libraries */
#include<stdio.h>
#include<stdlib.h>
#include<unistd.h>
#include<string.h>
/* OS specific libraries */
#ifdef _WIN32
#include<windows.h>
#endif
#ifdef __linux
#include<dlfcn.h>
#endif
/* Include D2XX header*/
#include "ftd2xx.h"
/* Include libMPSSE header */
//#include "libMPSSE_i2c.h"
/******************************************************************************/
const BYTE MSB_FALLING_EDGE_CLOCK_BYTE_IN = '\x24';
const BYTE MSB_FALLING_EDGE_CLOCK_BYTE_OUT = '\x11';
const BYTE MSB_RISING_EDGE_CLOCK_BIT_IN = '\x22';
FT_STATUS ftStatus; //Status defined in D2XX to indicate operation result
FT_HANDLE ftHandle; //Handle of FT2232H device port
BYTE OutputBuffer[1024]; //Buffer to hold MPSSE commands and data to be sent to FT2232H
BYTE InputBuffer[1024]; //Buffer to hold Data bytes to be read from FT2232H
DWORD dwClockDivisor = 0x012B; //Value of clock divisor, SCL Frequency = 60/((1+0x012B)*2) (MHz) = 100khz
DWORD dwNumBytesToSend = 0; //Index of output buffer
DWORD dwNumBytesSent = 0, dwNumBytesRead = 0, dwNumInputBuffer = 0;
//////////////////////////////////////////////////////////////////////////////////////
// Below function will setup the START condition for I2C bus communication. First, set SDA, SCL high and ensure hold time
// requirement by device is met. Second, set SDA low, SCL high and ensure setup time requirement met. Finally, set SDA, SCL low
////////////////////////////////////////////////////////////////////////////////////////
void HighSpeedSetI2CStart(void)
{
DWORD dwCount;
for(dwCount=0; dwCount < 4; dwCount++) // Repeat commands to ensure the minimum period of the start hold time ie 600ns is achieved
{
OutputBuffer[dwNumBytesToSend++] = '\x80'; //Command to set directions of lower 8 pins and force value on bits set as output
OutputBuffer[dwNumBytesToSend++] = '\x03'; //Set SDA, SCL high, WP disabled by SK, DO at bit „1‟, GPIOL0 at bit „0‟
OutputBuffer[dwNumBytesToSend++] = '\x03'; //Set SK,DO,GPIOL0 pins as output with bit „1‟, other pins as input with bit „0‟
}
for(dwCount=0; dwCount < 4; dwCount++) // Repeat commands to ensure the minimum period of the start setup time ie 600ns is achieved
{
OutputBuffer[dwNumBytesToSend++] = '\x80'; //Command to set directions of lower 8 pins and force value on bits set as output
OutputBuffer[dwNumBytesToSend++] = '\x01'; //Set SDA low, SCL high, WP disabled by SK at bit „1‟, DO, GPIOL0 at bit „0‟
OutputBuffer[dwNumBytesToSend++] = '\x03'; //Set SK,DO,GPIOL0 pins as output with bit „1‟, other pins as input with bit „0‟
}
OutputBuffer[dwNumBytesToSend++] = '\x80'; //Command to set directions of lower 8 pins and force value on bits set as output
OutputBuffer[dwNumBytesToSend++] = '\x00'; //Set SDA, SCL low, WP disabled by SK, DO, GPIOL0 at bit „0‟
OutputBuffer[dwNumBytesToSend++] = '\x03'; //Set SK,DO,GPIOL0 pins as output with bit „1‟, other pins as input with bit „0‟
}
//////////////////////////////////////////////////////////////////////////////////////
// Below function will setup the STOP condition for I2C bus communication. First, set SDA low, SCL high and ensure setup time
// requirement by device is met. Second, set SDA, SCL high and ensure hold time requirement met. Finally, set SDA, SCL as input
// to tristate the I2C bus.
////////////////////////////////////////////////////////////////////////////////////////
void HighSpeedSetI2CStop(void)
{
DWORD dwCount;
for(dwCount=0; dwCount<4; dwCount++) // Repeat commands to ensure the minimum period of the stop setup time ie 600ns is achieved
{
OutputBuffer[dwNumBytesToSend++] = '\x80'; //Command to set directions of lower 8 pins and force value on bits set as output
OutputBuffer[dwNumBytesToSend++] = '\x01'; //Set SDA low, SCL high, WP disabled by SK at bit „1‟, DO, GPIOL0 at bit „0‟
OutputBuffer[dwNumBytesToSend++] = '\x03'; //Set SK,DO,GPIOL0 pins as output with bit „1‟, other pins as input with bit „0‟
}
for(dwCount=0; dwCount<4; dwCount++) // Repeat commands to ensure the minimum period of the stop hold time ie 600ns is achieved
{
OutputBuffer[dwNumBytesToSend++] = '\x80'; //Command to set directions of lower 8 pins and force value on bits set as output
OutputBuffer[dwNumBytesToSend++] = '\x03'; //Set SDA, SCL high, WP disabled by SK, DO at bit „1‟, GPIOL0 at bit „0‟
OutputBuffer[dwNumBytesToSend++] = '\x03'; //Set SK,DO,GPIOL0 pins as output with bit „1‟, other pins as input with bit „0‟
}
//Tristate the SCL, SDA pins
OutputBuffer[dwNumBytesToSend++] = '\x80'; //Command to set directions of lower 8 pins and force value on bits set as output
OutputBuffer[dwNumBytesToSend++] = '\x00'; //Set WP disabled by GPIOL0 at bit „0‟
OutputBuffer[dwNumBytesToSend++] = '\x00'; //Set GPIOL0 pins as output with bit „1‟, SK, DO and other pins as input with bit „0‟
}
//////////////////////////////////////////////////////////////////////////////////////
// Below function will send a data byte to I2C-bus EEPROM 24LC256, then check if the ACK bit sent from 24LC256 device can be received.
// Return true if data is successfully sent and ACK bit is received. Return false if error during sending data or ACK bit can‟t be received
//////////////////////////////////////////////////////////////////////////////////////
BOOL SendByteAndCheckACK(BYTE dwDataSend)
{
FT_STATUS ftStatus = FT_OK;
OutputBuffer[dwNumBytesToSend++] = MSB_FALLING_EDGE_CLOCK_BYTE_OUT; //Clock data byte out on –ve Clock Edge MSB first
OutputBuffer[dwNumBytesToSend++] = '\x00';
OutputBuffer[dwNumBytesToSend++] = '\x00'; //Data length of 0x0000 means 1 byte data to clock out
OutputBuffer[dwNumBytesToSend++] = dwDataSend; //Add data to be send
//Get Acknowledge bit from EEPROM
OutputBuffer[dwNumBytesToSend++] = '\x80'; //Command to set directions of lower 8 pins and force value on bits set as output
OutputBuffer[dwNumBytesToSend++] = '\x00'; //Set SCL low, WP disabled by SK, GPIOL0 at bit „0‟
OutputBuffer[dwNumBytesToSend++] = '\x01'; //Set SK, GPIOL0 pins as output with bit „1‟, DO and other pins as input with bit „0‟
OutputBuffer[dwNumBytesToSend++] = MSB_RISING_EDGE_CLOCK_BIT_IN; //Command to scan in ACK bit , -ve clock Edge MSB first
OutputBuffer[dwNumBytesToSend++] = '\x0'; //Length of 0x0 means to scan in 1 bit
OutputBuffer[dwNumBytesToSend++] = '\x87'; //Send answer back immediate command
ftStatus = FT_Write(ftHandle, OutputBuffer, dwNumBytesToSend, &dwNumBytesSent); //Send off the commands
dwNumBytesToSend = 0; //Clear output buffer
//Check if ACK bit received, may need to read more times to get ACK bit or fail if timeout
ftStatus = FT_Read(ftHandle, InputBuffer, 1, &dwNumBytesRead); //Read one byte from device receive buffer
if ((ftStatus != FT_OK) || (dwNumBytesRead == 0))
{ return FALSE; /*Error, can't get the ACK bit from EEPROM */ }
else
if (((InputBuffer[0] & BYTE('\x1')) != BYTE('\x0')) ) //Check ACK bit 0 on data byte read out
{ return FALSE; /*Error, can't get the ACK bit from EEPROM */ }
OutputBuffer[dwNumBytesToSend++] = '\x80'; //Command to set directions of lower 8 pins and force value on bits set as output
OutputBuffer[dwNumBytesToSend++] = '\x02'; //Set SDA high, SCL low, WP disabled by SK at bit '0', DO, GPIOL0 at bit '1'
OutputBuffer[dwNumBytesToSend++] = '\x03'; //Set SK,DO,GPIOL0 pins as output with bit „1‟, other pins as input with bit „0‟
return TRUE;
}
DWORD dwCount;
//Try to open the FT2232H device port and get the valid handle for subsequent access
char SerialNumBuf[64];
ftStatus = FT_ListDevices((PVOID)0,& SerialNumBuf, FT_LIST_BY_INDEX|FT_OPEN_BY_SERIAL_NUMBER);
ftStatus = FT_OpenEx((PVOID) SerialNumBuf, FT_OPEN_BY_SERIAL_NUMBER, &ftHandle);
if (ftStatus == FT_OK)
{
// Port opened successfully
ftStatus |= FT_ResetDevice(ftHandle); //Reset USB device
//Purge USB receive buffer first by reading out all old data from FT2232H receive buffer
ftStatus |= FT_GetQueueStatus(ftHandle, &dwNumInputBuffer); // Get the number of bytes in the FT2232H receive buffer
if ((ftStatus == FT_OK) && (dwNumInputBuffer > 0))
FT_Read(ftHandle, &InputBuffer, dwNumInputBuffer, &dwNumBytesRead); //Read out the data from FT2232H receive buffer
ftStatus |= FT_SetUSBParameters(ftHandle, 65536, 65535); //Set USB request transfer size
ftStatus |= FT_SetChars(ftHandle, false, 0, false, 0); //Disable event and error characters
ftStatus |= FT_SetTimeouts(ftHandle, 0, 5000); //Sets the read and write timeouts in milliseconds for the FT2232H
ftStatus |= FT_SetLatencyTimer(ftHandle, 16); //Set the latency timer
ftStatus |= FT_SetBitMode(ftHandle, 0x0, 0x00); //Reset controller
ftStatus |= FT_SetBitMode(ftHandle, 0x0, 0x02); //Enable MPSSE mode
if (ftStatus != FT_OK)
{ /*Error on initialize MPSEE of FT2232H*/ }
Sleep(50); // Wait for all the USB stuff to complete and work
//////////////////////////////////////////////////////////////////
// Below codes will synchronize the MPSSE interface by sending bad command „xAA‟ and checking if the echo command followed by
// bad command „AA‟ can be received, this will make sure the MPSSE interface enabled and synchronized successfully
//////////////////////////////////////////////////////////////////
OutputBuffer[dwNumBytesToSend++] = '\xAA'; //Add BAD command „xAA‟
ftStatus = FT_Write(ftHandle, OutputBuffer, dwNumBytesToSend, &dwNumBytesSent); // Send off the BAD commands
dwNumBytesToSend = 0; //Clear output buffer
do
{
ftStatus = FT_GetQueueStatus(ftHandle, &dwNumInputBuffer); // Get the number of bytes in the device input buffer
}while ((dwNumInputBuffer == 0) && (ftStatus == FT_OK)); //or Timeout
bool bCommandEchod = false;
ftStatus = FT_Read(ftHandle, &InputBuffer, dwNumInputBuffer, &dwNumBytesRead); //Read out the data from input buffer
for (dwCount = 0; dwCount < dwNumBytesRead - 1; dwCount++) //Check if Bad command and echo command received
{
if ((InputBuffer[dwCount] == BYTE('\xFA')) && (InputBuffer[dwCount+1] == BYTE('\xAA')))
{
bCommandEchod = true;
break;
}
}
if (bCommandEchod == false)
{ /*Error, can‟t receive echo command , fail to synchronize MPSSE interface;*/ }
////////////////////////////////////////////////////////////////////
//Configure the MPSSE settings for I2C communication with 24LC256
//////////////////////////////////////////////////////////////////
OutputBuffer[dwNumBytesToSend++] = '\x8A'; //Ensure disable clock divide by 5 for 60Mhz master clock
OutputBuffer[dwNumBytesToSend++] = '\x97'; //Ensure turn off adaptive clocking
OutputBuffer[dwNumBytesToSend++] = '\x8D'; //Enable 3 phase data clock, used by I2C to allow data on both clock edges
ftStatus = FT_Write(ftHandle, OutputBuffer, dwNumBytesToSend, &dwNumBytesSent); // Send off the commands
dwNumBytesToSend = 0; //Clear output buffer
OutputBuffer[dwNumBytesToSend++] = '\x80'; //Command to set directions of lower 8 pins and force value on bits set as output
OutputBuffer[dwNumBytesToSend++] = '\x03'; //Set SDA, SCL high, WP disabled by SK, DO at bit „1‟, GPIOL0 at bit „0‟
OutputBuffer[dwNumBytesToSend++] = '\x13'; //Set SK,DO,GPIOL0 pins as output with bit ‟, other pins as input with bit „‟
// The SK clock frequency can be worked out by below algorithm with divide by 5 set as off
// SK frequency = 60MHz /((1 + [(1 +0xValueH*256) OR 0xValueL])*2)
OutputBuffer[dwNumBytesToSend++] = '\x86'; //Command to set clock divisor
OutputBuffer[dwNumBytesToSend++] = dwClockDivisor & '\xFF'; //Set 0xValueL of clock divisor
OutputBuffer[dwNumBytesToSend++] = (dwClockDivisor >> 8) & '\xFF'; //Set 0xValueH of clock divisor
ftStatus = FT_Write(ftHandle, OutputBuffer, dwNumBytesToSend, &dwNumBytesSent); // Send off the commands
dwNumBytesToSend = 0; //Clear output buffer
Sleep(20); //Delay for a while
//Turn off loop back in case
OutputBuffer[dwNumBytesToSend++] = '\x85'; //Command to turn off loop back of TDI/TDO connection
ftStatus = FT_Write(ftHandle, OutputBuffer, dwNumBytesToSend, &dwNumBytesSent); // Send off the commands
dwNumBytesToSend = 0; //Clear output buffer
Sleep(30); //Delay for a while
}
BOOL bSucceed = TRUE;
BYTE ByteAddressHigh = 0x00;
BYTE ByteAddressLow = 0x80; //Set program address is 0x0080 as example
BYTE ByteDataToBeSend = 0x5A; //Set data byte to be programmed as example
HighSpeedSetI2CStart(); //Set START condition for I2C communication
bSucceed = SendByteAndCheckACK(0xAE); //Set control byte and check ACK bit. bit 4-7 of control byte is control code,
// bit 1-3 of „111‟ as block select bits, bit 0 of „0‟represent Write operation
bSucceed = SendByteAndCheckACK(ByteAddressHigh); //Send high address byte and check if ACK bit is received
bSucceed = SendByteAndCheckACK(ByteAddressLow); //Send low address byte and check if ACK bit is received
bSucceed = SendByteAndCheckACK(ByteDataToBeSend); //Send data byte and check if ACK bit is received
HighSpeedSetI2CStop(); //Set STOP condition for I2C communication
//Send off the commands
ftStatus = FT_Write(ftHandle, OutputBuffer, dwNumBytesToSend, &dwNumBytesSent);
dwNumBytesToSend = 0; //Clear output buffer
Sleep(50); //Delay for a while to ensure EEPROM program is completed
これが私が描いた回路図です