CY8C4xxx / CYBLExxxx series

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Securing device after programming

The Cypress CY8C4xxx and CYBLExxxx series devices provide chip-level protection which allows "permanent" protection of the device concerning read and write access. The sequence, to secure the device consists of multiple read / write accesses to special function registers of the CY8C4xxx and CYBLExxxx series devices.

Via J-Flash / Flasher ARM

The sequence to secure the device, needs to be added to the exit-steps of the J-Flash project. The exit steps will be executed at the end of an successful auto-programming process (Target -> Auto). J-Flash comes with an example project for the Cypress CYBLE-214009-00 device which contains a secure device programming sequence (File:Cypress CYBLE 214009-00.jflash). This sequence applies for all Cypress CY8C4xxx and CYBLExxxx series devices since they are compatible regarding secure procedure and can be adapted to fit custom requirements, by re-selecting the required device within the J-Flash project.

Wiki-Cypress CY8C4xxx CYBLExxxx ProtectCPU.png


Unsecuring device before reprogramming

The Cypress CY8C4xxx and CYBLExxxx series devices provide chip-level protection which allows "permanent" protection of the device concerning read and write access. The sequence, to unsecure the device consists of multiple read / write accesses to special function registers of the Cypress CY8C4xxx and CYBLExxxx series devices MCU.

Via J-Flash / Flasher ARM

J-Flash(v6.31k and following) detects if the device is secured. In case of a secured device a pop-up window occurs with request to unsecure the device. This sequence applies for all Cypress CY8C4xxx and CYBLExxxx series devices since they are compatible regarding secure procedure.