5.5.1.6 Boot External Notification I/O Pin Fuse

The default value given in this fuse description is the factory-programmed value and must not be mistaken for the Reset value.

Name:	BOOT_GPIOSEL
Offset:	0x0028
Reset:	0xFFFFFFFF
Property:	R/W

The bit fields in this fuse select the pin and its signal properties for the Boot External Notification signal at start-up.


Bit	31	30	29	28	27	26	25	24

Access
Reset


Bit	23	22	21	20	19	18	17	16
				SLEWLIM	ODRAIN		POL
Access				R/W	R/W		R/W
Reset				1	1		1


Bit	15	14	13	12	11	10	9	8
					GPIOPORTSEL[3:0]
Access					R/W	R/W	R/W	R/W
Reset					1	1	1	1


Bit	7	6	5	4	3	2	1	0
	ENABLE			GPIOPINSEL[4:0]
Access	R/W			R/W	R/W	R/W	R/W	R/W
Reset	1			1	1	1	1	1

Bit 20 – SLEWLIM Slew Rate Control for Boot External Notification Signal

This bit controls whether the slew rate is limited.

Value	Name	Description
0	FALSE	The slew rate is not limited (fast rise/fall time operation)
1	TRUE	The slew rate is limited.

Bit 19 – ODRAIN Open Drain Control for Boot External Notification Signal

This bit controls whether the fault source is of normal drive type or open-drain drive type. Together with the Pin Output Level for Boot External Notification Signal (POL) bit, the resulting behavior of the pin is as follows:


	ODRAIN = 0	ODRAIN = 1
POL = 0	Tristate	Drive high
POL = 1	Drive low	Drive low

Value	Name	Description
0	FALSE	The selected fault source is open drain drive
1	TRUE	The selected fault source is normal drive

Bit 17 – POL Select Polarity in Normal Drive Mode for Boot External Notification Signal

This bit selects whether the Boot External Notification signal is active-low or active-high. Refer also to the Open Drain Control for Boot External Notification Signal (ODRAIN) bit description, because ODRAIN and POL are interdependent properties for the pin.

Value	Name	Description
0	FALSE	The selected fault source is active-high
1	TRUE	The selected fault source is active-low

Bits 11:8 – GPIOPORTSEL[3:0] GPIO Port Select for Boot External Notification Signal

This bit field selects the I/O pin port used for the Boot External Notification signal.

Note: Select only a port that exists on the device.

Value	Name	Description
0x0	PORTA	Port A
0x1	PORTB	Port B
0x2	PORTC	Port C
0x3	PORTD	Port D
Other	-	No Boot External Notification signal used

Bit 7 – ENABLE Enable Boot External Notification Signal

This bit enables the Boot External Notification signal.

Value	Name	Description
0	DISABLE	The Boot External Notification signal is disabled
1	ENABLE	The Boot External Notification signal is enabled

Bits 4:0 – GPIOPINSEL[4:0] GPIO Pin Select for Boot External Notification Signal

This bit field selects the I/O pin used for the Boot External Notification signal.

Note: Select only a pin that exists on the device.

Value	Name	Description
0x00	PIN00	Pin 0
0x01	PIN01	Pin 1
...	...	...
0x1E	PIN30	Pin 30
0x1F	PIN31	Pin 31