Hi,
Note: The below explanation is regarding how the different number of EEPROMs connected to FX3 can get programmed
with firmware.
If the below explanation is not clear then please post your EEPROM size and which manufacturer, for us to explain with that particular case.
1. The default Bootloader initially looks for the EEPROM with slave address 0xA0 for
the firmware. This can't be changed.
2. The image(which may be part of the entire firmware) contains in it's second byte about
the information of what kind of EEPROM is connected.
The types of EEPROM are listed in the Boot format section of FX3 Programmer's Manual.
3. Once the firmware in the first EEPROM (with address 0xA0) is read by the bootloader, it
should address the next EEPROM if required which is there on the I2C bus.
4. The addressing of the next EEPROM is same for many EEPROMs except one version of Microchip
EEPROMs.
How the firmware is programmed into different EEPROMs connected to FX3 on I2C Bus:
Please find the below snippet of 'Control Center' windows C# application which has capability
to program the EEPROMs:
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unsafe internal FX3_FWDWNLOAD_ERROR_CODE DownloadUserIMGtoI2CE2PROM(ref byte[] buf, ref uint buflen)
{
int STAGE_SIZE = CyConst.CONTROLTFRER_DATA_LENGTH;
byte[] downloadbuf = new byte[STAGE_SIZE];
int NoOfStage = ((int)buflen / STAGE_SIZE);
int LastStage = ((int)buflen % STAGE_SIZE);
uint DownloadAddress = 0;
int FwImagePtr = 0;
int StageSize = STAGE_SIZE;
int maxpkt = ControlEndPt.MaxPktSize;
//Get the I2C addressing size
byte ImgI2CSizeByte = buf[2]; // the 2nd byte of the IMG file will tell us the I2EPROM internal addressing.
uint AddresingStageSize = 0;
ImgI2CSizeByte = (byte)((ImgI2CSizeByte >> 1) & 0x07); // Bit3:1 represent the addressing
bool IsMicroShipE2Prom = false;
switch (ImgI2CSizeByte)
{
case 0:
case 1:
return FX3_FWDWNLOAD_ERROR_CODE.I2CE2PROM_UNKNOWN_I2C_SIZE;
case 2:
AddresingStageSize = (4 * 1024); // 4KByte
break;
case 3:
AddresingStageSize = (8 * 1024); // 8KByte
break;
case 4:
AddresingStageSize = (16 * 1024); // 16KByte
break;
case 5:
AddresingStageSize = (32 * 1024); // 32KByte
break;
case 6:
AddresingStageSize = (64 * 1024); // 64KByte
break;
case 7:
IsMicroShipE2Prom = true; // 128KByte Addressing for Microchip.
AddresingStageSize = (64 * 1024); // 64KByte // case 7 represent 128Kbyte but it follow 64Kbyte addressing
break;
default:
return FX3_FWDWNLOAD_ERROR_CODE.I2CE2PROM_UNKNOWN_I2C_SIZE;
}
ControlEndPt.TimeOut = 5000;
ControlEndPt.Target = CyConst.TGT_DEVICE;
ControlEndPt.ReqType = CyConst.REQ_VENDOR;
ControlEndPt.Direction = CyConst.DIR_TO_DEVICE;
ControlEndPt.ReqCode = 0xBA;
ControlEndPt.Value = (ushort)(DownloadAddress & 0x0000FFFF); // Get 16-bit LSB
ControlEndPt.Index = (ushort)(DownloadAddress >> 16); // Get 16-bit MSB
for (uint i = 0; i < NoOfStage; i++)
{
//Copy data from main buffer to tmp buffer
for (uint j = 0; j < STAGE_SIZE; j++)
downloadbuf = buf[FwImagePtr + j];
if (!ControlEndPt.XferData(ref downloadbuf, ref StageSize))
{
return FX3_FWDWNLOAD_ERROR_CODE.FAILED;
}
ControlEndPt.Index += (ushort)StageSize; //Starting address withing I2C chunk size(for I2C size :32Kbyte the Index will go like 0,4,8,12,16 etc..)
FwImagePtr += STAGE_SIZE; //post transfer increament of buffer pointer
// Address calculation done in the below box
if (IsMicroShipE2Prom)
{//Microchip Addressing(0-(1-64),4(64 to 128),1(128 to 192 ),5(192 to 256))
if (FwImagePtr >= (128 * 1024))
{
if ((FwImagePtr % AddresingStageSize) == 0)
{
if (ControlEndPt.Value == 0x04)
ControlEndPt.Value = 0x01;
else
ControlEndPt.Value = 0x05;
ControlEndPt.Index = 0;
}
}
else if ((FwImagePtr % AddresingStageSize) == 0)
{
ControlEndPt.Value = 0x04;
ControlEndPt.Index = 0;
}
}
else
{//ATMEL addressing sequential
if ((FwImagePtr % AddresingStageSize)==0)
{// Increament the Value field to represent the address and reset the Index value to zero.
ControlEndPt.Value += 0x01;
if(ControlEndPt.Value>=8)
ControlEndPt.Value = 0x0; //reset the Address to ZERO
ControlEndPt.Index = 0;
}
}
}
if (LastStage != 0)
{//check for last stage
for (uint j = 0; j < LastStage; j++)
downloadbuf = buf[FwImagePtr + j];
if ((LastStage % maxpkt) != 0)
{// make it multiple of max packet size
int diff = (maxpkt - (LastStage % maxpkt));
for (int j = LastStage; j < (LastStage + diff); j++)
downloadbuf = 0;
LastStage += diff;
}
if (!ControlEndPt.XferData(ref downloadbuf, ref LastStage))
{
return FX3_FWDWNLOAD_ERROR_CODE.FAILED;
}
/*Failure Case:
The device does not return failure message when file size is more than 128KByte and only one 128Byte E2PROM on the DVK.
Solution:
Read back the last stage data to confirm that all data transferred successfully.*/
ControlEndPt.ReqCode = 0xBB;
ControlEndPt.Direction = CyConst.DIR_FROM_DEVICE;
if (!ControlEndPt.XferData(ref downloadbuf, ref LastStage))
{
return FX3_FWDWNLOAD_ERROR_CODE.FAILED;
}
}
return FX3_FWDWNLOAD_ERROR_CODE.SUCCESS;
}
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5. The above code along with the previous comment can be referred to understand how the EEPROMs gets programmed by the Host Application.
The special case of Microchip addressing is discussed below:
- As can be seen from the above code,
a. Addressing scheme can be known by reading the second byte of the image. In the above code the variable ImgI2CSizeByte tells that.
b. For example if you are using Microchip 128KB EEPROM (24AA1025/24LC1025/24FC1025) then the first 1-64 KB of the first EEPROM on the bus
is addressed by 0xA0
c. Then the second half (64-128)KB of the first EEPROM is addressed by 0xA4
(Refer this comment in the above code: //Microchip Addressing(0-(1-64),4(64 to 128),1(128 to 192 ),5(192 to 256)))
d. Similarly the first part of second EEPROM is addressed by 0xA1 and second half by 0xA5
Also please refer to below link for 24LC1025 part datasheet to get clear idea on addressing of the EEPROM:
http://ww1.microchip.com/downloads/en/DeviceDoc/21941E.pdf
Note: When multiple EEPROMs are used the A2, A1, A0, B0 pins whichever applicable to the EEPROM being used needs to be correctly pulled high/low for it to get properly addressed.
Regards,
Hemanth
Hemanth
