SAM3X 4X X7X

Black Magic Probe supports a lot of targets from many manufacturers. Despite the effort to provide a unified way of handling the targets, some specificities exist. This page documents some of them.

Commands

gpnvm (get|set)

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Get

Show the current status of GPNVM bits

gpnvm get

(gdb) monitor gpnvm get
GPNVM: 0x00000040

Set

Set or clear the masked GPNVM bits

Valid bits range from 0 to 8 (see table)

gpnvm set <mask> <value>

(gdb) monitor gpnvm set 0x180 0x180
GPNVM: 0x000001C0

Bits

SAMX7X

GPNVM Bit	Function	Values
0	Security bit	0: disabled
		1: enabled
1	Boot mode selection	0: ROM
		1: Flash
5:2	Free
6	Reserved
8:7*	TCM configuration	00: 0 Kbytes DTCM + 0 Kbytes ITCM (default)
		01: 32 Kbytes DTCM + 32 Kbytes ITCM
		10: 64 Kbytes DTCM + 64 Kbytes ITCM
		11: 128 Kbytes DTCM + 128 Kbytes ITCM

*Note: these bits only take effect after a reset, changing this via th gpnvm command will reset the target automatically