2117 - MachXO2: Can I connect the JTAGENB pin of the MachXO2 device directly to the VCC or GND?
The JTAG ENABLE pin of MachXO2 is an optional input pin that can be used to control the function of the ispJTAG port during user mode. By default, the JTAGENB pin is a user I/O while the 4-wire ispJTAG port is used as a dedicated programming port. This is the traditional JTAG port configuration that is available for blank devices and devices programmed with default software sysCONFIG attribute settings.
When the ispJTAG port is to be recovered as a user I/O, the sysCONFIG attribute JTAG_PORT must be set to DISABLE. Under this condition the JTAGENB pin becomes dedicated. A low signal on the JTAGENB will disable the JATG port and the 4 JTAG pins become user I/O. A high signal on the JTAGENB will enable the JTAG port and the 4 pins become dedicated JTAG pins.
For more details, please refer to the MachXO2 Programming and Configuration User Guide. The downloadable link can be found here: https://www.latticesemi.com/view_document?document_id=39085
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