Apple Intelligence is now available on iPhone, iPad, and Mac!

📢 Newsroom Update

Apple’s new MacBook Pro features the incredibly powerful M4 family of chips and ushers in a new era with Apple Intelligence. Learn more >

📢 Newsroom Update

Apple introduces M4 Pro and M4 Max. Learn more >

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

what is interface crc error write DMA EXT ?

what is interface crc error write DMA EXT ?


I've got 3 of these errors after running SMART utility.


everytime I type I get a beach ball.


please help.

MacBook Pro, macOS Sierra (10.12.3)

Posted on Mar 7, 2017 5:06 PM

Reply
Question marked as Top-ranking reply

Posted on Mar 7, 2017 7:29 PM

CRC is cyclic redundancy check. It is a type of checksum used to detect errors on block transfers of data.


DMA is Direct Memory Access. Once disk drives got too fast to pass one word at a time through the processor, they did their transfers using DMA hardware, which stores or fetches that data directly from or to memory with no processor intervention, then gives the processor an "I'm done"Interrupt at the end.


EXT could be Extent, what blocks on a disk are taken up by a file, or it could be external, a reference to a drive outside your Mac.


If this is on transfers from/to the Internal Boot Drive, I would be suspicious that you were developing a bad SATA cable. Some MacBooks have seen this where the Internal SATA cable scrubs against the machined inside surface of the case.

1 reply
Question marked as Top-ranking reply

Mar 7, 2017 7:29 PM in response to joshmartinez

CRC is cyclic redundancy check. It is a type of checksum used to detect errors on block transfers of data.


DMA is Direct Memory Access. Once disk drives got too fast to pass one word at a time through the processor, they did their transfers using DMA hardware, which stores or fetches that data directly from or to memory with no processor intervention, then gives the processor an "I'm done"Interrupt at the end.


EXT could be Extent, what blocks on a disk are taken up by a file, or it could be external, a reference to a drive outside your Mac.


If this is on transfers from/to the Internal Boot Drive, I would be suspicious that you were developing a bad SATA cable. Some MacBooks have seen this where the Internal SATA cable scrubs against the machined inside surface of the case.

what is interface crc error write DMA EXT ?

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.