Lattice Semiconductor MachXO2 Programming And Configuration Usage Manual page 35

MachXO2 Programming and Configuration Usage Guide
USERCODE
The MachXO2 Configuration Flash sector contains a 32-bit register for storing a user-defined value. The default
value stored in the register is 0x00000000. Using the USERCODE preference you can assign any value to the reg-
ister you desire. Suggested uses include the configuration data version number, a manufacturing ID code, date of
assembly, or the JEDEC file checksum.
The format of the USERCODE field is controlled using the USERCODE_FORMAT preference. Data entry can be
performed in either Binary, Hex, or ASCII formats.
USERCODE_FORMAT
The USERCODE_FORMAT preference selects the format for the data field used to assign a value in the USER-
CODE preference. The USERCODE_FORMAT has three options:
• Binary – USERCODE is set using 32 '1' or '0' characters.
• Hex – USERCODE is set using eight hexadecimal digits (i.e., 0-9A-F)
• ASCII – USERCODE is set using up to four ASCII characters
CUSTOM_IDCODE
The CUSTOM_IDCODE preference is used to assign a 32-bit register that resides in the Feature Row. The
CUSTOM_IDCODE field is only active when the MY_ASSP preference is in the ON state. The value assigned can
be entered in binary or hexadecimal, according to the CUSTOM_IDCODE_FORMAT preference. See the
MY_ASSP section for more information about how to assign a value to the CUSTOM_IDCODE preference.
CUSTOM_IDCODE_FORMAT
The CUSTOM_IDCODE_FORMAT preference selects the format for the data field used to assign a value in the
CUSTOM_IDCODE preference. The CUSTOM_IDCODE_FORMAT has two options:
• Binary – CUSTOM_IDCODE is set using 32 '1' or '0' characters.
• Hex – CUSTOM_IDCODE is set using eight hexadecimal digits (i.e., 0-9A-F)
SHAREDEBRINIT
When set to ENABLE, this preference allows one copy of a unique memory initialization file to be stored in the
Flash memory. This copy of the initialization values can be shared among multiple EBRs. Doing so reduces the bit-
stream size of the design and saves UFM space for other applications.
MUX_CONFIGURATION_PORTS
The MUX_CONFIGURATION_PORTS is used in the event that all configuration ports are disabled. Disabling all of
the available configuration ports turns the MachXO2 into a "write one time" device.
MUX_CONFIGURATION_PORTS confirms the removal of all configuration ports. The control is only active when
all of the other configuration ports are set to the DISABLE state. MUX_CONFIGURATION_PORTS set to the
ENABLE state enables the JTAGENB input pin, permitting the JTAG port pins to be multiplexed. Setting
MUX_CONFIGURATION_PORTS to the DISABLE state causes the Diamond build tools to honor the removal of all
other configuration ports, allowing the MachXO2 to become a "write one time" device.
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