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→ATE and EFUSE
== ATE and EFUSE ==
The CEC1702 may ship ships in ATE mode from other suppliers, which prevents booting off of SPI flash and seems to mess with the UART baud rate (57600 baud corresponded to 32000 baud). Note the CW308T-CEC1702 target boards have this disabled as part of the production process / test procedure. The device can be changed into normal mode by setting Byte 35 Bit[7] of the EFUSE memory. This can be done via an external SPI flash such as the mikroProg, or by loading a program that modifies the bits via JTAG. For additional information, see the CEC1702 datasheet and errata. Before modifying the EFUSE, keep the following in mind:
* EFUSE bits are one time programmable (OTP) to 1. This means there's no way to set the bits back to 0 once they are set to 1.
* To modify the EFUSE, VREF must be set to between 1.52V and 1.6V.
* Note that both the EFUSE instructions in the CEC1702 datasheet and mikroC PRO's EFUSE program rely on VREF being set to ground while FSOURCE_EN_READ and FSOURCE_EN_PRGM are being switched. Instead, to modify the EFUSE, set both to 0, wait for the registers to be set, then set the appropriate bit.
* Some additional features of the EFUSE include setting keys for flash decryption and authentication by the bootloader.
You can see an example program that works with the CW308T-CEC1702 device at [https://github.com/newaetech/chipwhisperer-target-cec1702]
== Useful Links ==