topic Re: FRDM K64F SPI clock pin problem in Kinetis Microcontrollers

FRDM K64F SPI clock pin problem

vubdub — Mon, 18 Aug 2014 16:44:18 GMT

Hello.

I have trouble with serial communication between FRDM K64F and LCD 5110.

When FRDM SPI clock pin (PTD1) is connected to LCD's clock input simply via wire then clock signal stay always low. But if you touch this clock chain in any point by some conductive object (e. g. scope probe or screwdriver) or add to pin some pull-down resistor and reset the board then SPI clock will be generated and LCD work fine.

Re: FRDM K64F SPI clock pin problem

Hui_Ma — Fri, 22 Aug 2014 02:28:17 GMT

Hi,

If the FRDM-K64F has the same digital GND with LCD 5110 board? That could be a root cause.

Wish it helps.
best regards
Ma Hui

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Re: FRDM K64F SPI clock pin problem

vubdub — Fri, 22 Aug 2014 17:42:40 GMT

here is my wiring

https://docs.google.com/file/d/0B8Ca28cJlc3rbnlFTzFXM2NPM1k/edit

I also tried to connect display ground to another GND pins on FRDM but it doesn't solve the problem.