CC2640R2F: minmum time definition for valid level of pin for ROM boot

JiCheng_ZhangXiang

Part Number: CC2640R2F
Other Parts Discussed in Thread: CC2640

Hello, TI, Could you introduce the time define for the pin level for ROM boot? I don't know the miniumum time definition for the valid level of the pin config for boot.

over 3 years ago

0 Ryan Brown1 over 3 years ago

TI__Guru**** 217617 points

Hello JiCheng,

RESET_N should be low for at least 1 μs, after which time device restarts and evaluates the BL_CONFIG values stored in the CCFG.

Regards,
Ryan

0 JiCheng_ZhangXiang over 3 years ago in reply to Ryan Brown1

Intellectual 255 points

How about the BL_pin valid level keep time? the same as Reset_N? at least 1us?

0 JiCheng_ZhangXiang over 3 years ago in reply to Ryan Brown1

Intellectual 255 points

so, there must be case that 1 us valid wave occurs at BL_pin and reset_N at the same time, CC2640 must go to ROM boot mode?

0 Ryan Brown1 over 3 years ago in reply to JiCheng_ZhangXiang

TI__Guru**** 217617 points

The BL_pin needs to be kept at the valid level after the reset line is restored so that when the MCU boots it is able to determine whether to enter bootloader mode. The CC2640 will only know to enter the ROM bootloader if the CCFG has been configured properly. You can find out more from swra466.

Regards,
Ryan

Bluetooth®︎

Bluetooth forum

CC2640R2F: minmum time definition for valid level of pin for ROM boot