System Control Memory Registers
592
SLAU723A – October 2017 – Revised October 2018
Copyright © 2017–2018, Texas Instruments Incorporated
Internal Memory
The DBG0 bit is cleared by the factory and the DBG1 bit is set, which enables external debuggers.
Clearing the DBG1 bit disables any external debugger access to the device, starting with the next power-
up cycle of the device. The NW bit indicates that bits in the register can be changed from 1 to 0.
By committing the register values using the COMT bit in the FMC register, the register contents become
nonvolatile and are therefore retained following power cycling. Before being committed, bits can only be
changed from 1 to 0. All Reserved bits must remain as 1s. The reset value shown applies only to power-
on reset when the register is not yet committed; any other type of reset does not affect this register. After
it is committed, the register retains its value through power-on reset. When committed, the only way to
restore the factory default value of this register is to perform the sequence detailed in
.
BOOTCFG is shown in
and described in
Return to
Figure 7-43. BOOTCFG Register
31
30
29
28
27
26
25
24
NW
RESERVED
R-0x1
R-0x7FFF
23
22
21
20
19
18
17
16
RESERVED
R-0x7FFF
15
14
13
12
11
10
9
8
PORT
PIN
POL
EN
R-0x7
R-0x7
R-0x1
R-0x1
7
6
5
4
3
2
1
0
RESERVED
KEY
RESERVED
DBG1
DBG0
R-0x7
R-0x1
R-0x3
R-0x1
R-0x0
Table 7-45. BOOTCFG Register Field Descriptions
Bit
Field
Type
Reset
Description
31
NW
R
0x1
Not Written.
When set, this bit indicates that the values in this register can be
changed from 1 to 0.
When clear, this bit specifies that the contents of this register cannot
be changed.
30-16
RESERVED
R
0x7FFF
Ensure that the Reserved bits of this register are not changed from
the default of all 1s.
15-13
PORT
R
0x7
Boot GPIO Port.
This field selects the port of the GPIO port pin that enables the ROM
boot loader at reset. The selected port can be reprogrammed for a
different function after reset.
Note: Do not select PC0-3, PD7, or PE7, because they are locked by
default at reset.
0x0 = Port A
0x1 = Port B
0x2 = Port C
0x3 = Port D
0x4 = Port E
0x5 = Port F
0x6 = Port G
0x7 = Port H