LPC1788 Can UART wake from deep-sleep or power-down

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LPC1788 Can UART wake from deep-sleep or power-down

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NXP Employee
NXP Employee
Content originally posted in LPCWare by mengeriser on Thu Oct 25 11:36:05 MST 2012
Can the UART wake the 1788 from deep-sleep or power-down modes? 

This is from UM10470:

3.12.8 Wake-up from Reduced Power Modes
Any enabled interrupt can wake up the CPU from Sleep mode. Certain interrupts can
wake up the processor if it is in either Deep Sleep mode or Power-down mode.
Interrupts that can occur during Deep Sleep or Power-down mode will wake up the CPU if
the interrupt is enabled. After wake-up, execution will continue to the appropriate interrupt
service routine. These interrupts are NMI, External Interrupts EINT0 through EINT3, GPIO
interrupts, Ethernet Wake-on-LAN interrupt, Brownout Detect, RTC Alarm, CAN Activity
Interrupt, and USB Activity Interrupt. For the wake-up process to take place the
corresponding interrupt must be enabled in the NVIC. For pin-related peripheral functions,
the related functions must also be mapped to pins.

This seems to indicate no, but wanted confirmation. If not, is there another way to do it?  Tie UART pin to GPIO and use GPIO interrupt?

Thanks
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NXP Employee
NXP Employee
Content originally posted in LPCWare by noahk on Sat Nov 17 23:35:59 MST 2012
Hi Matt,

The recently released LPC800 family includes a new USART which is capable of waking up the CPU. The user manual refers to Synchronous Slave Mode which is capable of running the USART from an external clock and waking up the CPU.

http://www.nxp.com/documents/user_manual/UM10601.pdf
Chapter 15: 15.3.2.2 Wake-up from Deep-sleep or Power-down mode

Noah
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NXP Employee
NXP Employee
Content originally posted in LPCWare by Daniel Widyanto on Sun Oct 28 21:07:02 MST 2012
Hi mattfpga,

No, UART cannot be used to wake up from deep sleep and power down modes.

If you want to use UART to wake up, you can connect the UART RTS pin to the any of PORT0 or PORT2 pin, and enable the interrupt for that pin.
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