topic Re: Question on User Manual Rev. 1 - 12 Nov 2012: Page 8 Footnote 3: Do not use this pads for high-speed application such as SPI... in LPC Microcontrollers

Question on User Manual Rev. 1 - 12 Nov 2012: Page 8 Footnote 3: Do not use this pads for high-speed application such as SPI...

lpcware — Wed, 15 Jun 2016 20:10:50 GMT

Content originally posted in LPCWare by capiman on Tue Feb 19 02:12:55 MST 2013
I have a question regarding User Manual Rev. 1 - 12 Nov 2012:
On page 8 there is footnote 3: "Do not use this pads for high-speed application such as SPI or USART".

Are the pads PIO0_10 and PIO0_11 not useable at all for SPI or USART?
Or are they useable, but due to electrical characteristic (e.g. filters, ...), but only for low speed of SPI or USART?
If yes, what is the speed limit?

Is RS232 e.g. with 115200 or SPI with 400 kHz possible, because it is in the same range as I2C?

Re: Question on User Manual Rev. 1 - 12 Nov 2012: Page 8 Footnote 3: Do not use this pads for high-speed application such as SPI...

lpcware — Wed, 15 Jun 2016 20:10:51 GMT

Content originally posted in LPCWare by capiman on Tue Feb 19 07:07:57 MST 2013
Correction of my question: The footnote 3 is not in User Manual, but in Objective data sheet.
BTW: Same text in Objective data sheet Rev. 2 - 28 January 2013.

Re: Question on User Manual Rev. 1 - 12 Nov 2012: Page 8 Footnote 3: Do not use this pads for high-speed application such as SPI...

lpcware — Wed, 15 Jun 2016 20:10:52 GMT

Content originally posted in LPCWare by Wouter on Thu Feb 21 00:22:29 MST 2013
Hi Capiman,

PIO0_10 and PIO0_11 on the LPC800 are true open-drain outputs. When configured as an output, they require a pull-up resistor to set the pin high. The maximum speed will depend on the value of this pull-up resistor, and the loading on the pin. An UART @ 115200 baud or SPI at 400KHz should be no problem.

Regards,
Wouter