A part of i.MX7S eFuse could not be read.

[satoshishimoda]

Hi community,

Our customer tried reading a i.MX7S efuse, and succeeded reading lot number programmed in 0x410[31:0] and 0x420[10:0].
However, 0x420[31:11] was all "0".
According to Table 6-19 of IMX7DRM Rev.0.1, wafer number and X/Y coordinate should be programmed in the field.
They executed the process chapter 6.4.3.1.1 and 6.4.3.1.2, so we think the procedure was not wrong since they could read 0x410[31:0] and 0x420[10:0] correct.
Do think think why 0x420[31:11] cannot be read?

Best Regards,
Satoshi Shimoda

[igorpadykov · Accepted solution]

Hi Satoshi 

customer should use unique ID is a full 64bit value, even 0x420[31:11] was all "0" and

it is correct unique value. That was confirmed by app team (please create service request

for additional details). Additonal info provided: NXP does not provide the actual decoding to customers.

Best regards
igor
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