I have used Spansion's S34ML04G100s before with good success a few years ago, but I have one example that is powered & communicating but reporting unexpected results when requesting ONFI signature, ID, and parameters.
1. On requesting the signature with a 90h 20h command the reply is: 01 FC 90 95 00h, but I was expecting 4f 4E 46 49h ie "ONFI" .
2. On requesting the ICs ID with a 90h 00H command the reply is: 01 FC 90 95 74h Which means the manufacture's ID is believable (01) as is the flash technology (ie 90 95 74) but the FCh isnt listed in the datasheet in S3.16.
3. On requesting the parameters with an ECh 00H command the reply is believable and roughly tallies with the memory size and does report its an "ONFI" device made by spansion . (see attached debugger screen shot) although there are minor discrepancies with datasheet S3.19...Revision 2 being listed as reserved for example.
4. The first 3 blocks of the device are all reporting as factory bad blocks (FFh) as per s9.2 of the data sheet which is suspicious/unlucky. If I ignore these bad block warnings and attempt an erase/write/verify they do fail the verify test - so the bad block warning looks valid although worrying given 1, 2 & 3 above.
5. the markings on the IC appear to be: "spansion", "S34ML04G100TFI100", "829bb03 A", "(c) Spansion"
Given I have used these ICs before with good success is this is just a bad example that has escaped the factory QA and gone into circulation? Are these products regularly suffering the same issues seen?
As mentioned in the following link, https://www.cypress.com/news/cypress-announces-closing-joint-venture-transaction-sk-hynix-system-ic , Cypress NAND memory business is currently with SkyHigh memory. Please contact SkyHigh memory for support to use NAND devices.
Thanks and Regards,