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Subject: Need support on "Sequential Read"
Description:
Hi, I am trying to write and read to EEPROM. (Processor: freescale IMX6Q) I can read single byte successfully. Also, when i try to read EEPROM using Sequential Read (Multibyte read), i can read data bytes from 0 to 255, 256 to 511 etc (in multiple of 255 , ie: 0xFF) correctly. However, If i try read bytes: 0 to 511, i get correct value from 0 to 255, but wrong values from 256 to 511. What is the reason? and how i can correct it? Please reply asap.
Thanks.
Regards,
Keshava G N
Member - Technical, iWave Systems, Bangalore, India
An additional information:
Part number: CAT24AA16TDI-GT3
VCC = 1.8 v
Clock freq = 400kHz
I read/write happening correctly.
However, while using sequential read, in the boundaries of : FFh (ie: 255 in decimal) address (example: read values from 250 to 260), I get correct values only from 250 to 255, but get only FF from 256 to 260.
Please help to solve the issue.
A1:Would you please provide part number (EEPROM) are you referring to and more details about application conditions: VCC, Clock freq, etc?
A2: For this particular case, I have to check with you how you address the part when Reading in Sequential mode.
Per the device data sheet, the Memory space address requires 11 Address bits: : 8 bits are sent during the “ADDRESS byte” and 3 bits are part of the “Slave Address Byte” .
- So we need to make sure you have a correct combination for the a10, a9, a8 from the Slave Address byte. You need to start with a10, a9, a8 bits = 0, 0, 0.
The CAT24AA16 should be able to continue sending data out up to the end of Last Addr Byte = 0x7FF and when reaches the last address it will wrap around to zero (during Sequential Read).
- I cannot see any reason do not work this way, except inside there is a different memory size: maybe it is not a 16Kb memory !?
Can you provide Top package marking, Date Code..?
- Please provide also details like: customer name and application, if NEW design ..? Have you used our part before ..? How many parts are behaving in this way ..? etc ..
Answered by: ON Semiconductor
2013-02-12 09:34:32.089