56303 | 563xx | 5680 | 56805 | 5680x | 56F80 | 56F800DEMO | 56F805 | 56f807 | 56F830 | ADC | Bootloader | Codec | CodeWarrior | CW5 | CW6 | Debugger | DSP56303 | DSP56303EVM | DSP563xx | DSP5680 | DSP56800 | DSP56807 | DSP56858 | DSP56858EVM | DSP56F803 | DSP56F805 | DSP56F807 | DSP56F80x | DSP56F826 | DSP56F827 | DSP56F8xx | EVM | FFT | Flash_over_jtag | GPIO | Interrupt | Interrupts | JTAG | LCD | Linker | MCF5307 | Metrowerks | Modulus | MSCAN | PCMaster | PWM | Quad | Rif | RTOS | SDK | SPI

Taking Roelof Oelofsen's suggestion a little further, one could pin out the JTAG/OnCE connector differently and using a different connector than what Motorola uses. Additionally, a 0 Ohm resistor that ties TRST to RESET on your production boards would prevent a rogue using the debugger from working unless that person knew where and how the two lines were connected together. You'd still be able to debug your board, since the resistor is easily removed/replaced. (The debugger needs to independently assert RESET and TRST to be able to control the DSP.) A generous gob of epoxy over the DSP package (or at least the JTAG/OnCE pins) would prevent all but the most determined rogue from getting at your code. (If they have the technology and desire to remove the epoxy, they very likely have the ability to microprobe the device to get at the code, even if security were implemented inside the device...) The rogue would first have to remove the epoxy to trace back the JTAG/OnCE pins to the debug connector AND find the short between TRST and RESET before they could do anything useful with the device. The likelihood of a first pass success for someone unfamiliar with epoxy removal is low, so it would very likely take several tries with more than one of your application boards to yield success. --david

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Start your Android Ice Cream Sandwich development on TI's AM35x Sitara ARM Cortex-A8 processor today.



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