Logic level shifter, 74LVC245, connection issues, SPI

Hi all,

I seem to be having problems connecting my 74LVC245 74LVC245 - Breadboard Friendly 8-bit Logic Level Shifter : ID 735 : $1.50 : Adafruit Industries, Unique & fun DIY electronics and kits chip to my mkrzero and CAN shield. The Mkrzero runs at 3.3V and the CAN shield runs at 5V and I am trying to get them to communicate through an SPI interface.

No matter how I connect the pins I can only get the device to translate one way. Either 5V to 3.3 or 3.3 to 5 but not both at the same time. With the Dir and VCC both at 3.3 I can get a 5V signal to step down to 3.3 on the VCC side but a 3.3 signal or 5V signal on the other side is translated to zero. This is the same setup used in this tutorial tutorials:products:minicoloroled:index.html [AdaWiki] and it works.

With DIR at 5V and VCC at 3.3V a 3.3V signal and 5V signal on the VCC side both translate to 3.3.

With Dir at 3.3V and VCC at 5V a 5V signal on the VCC side is 0 on the DIR side while a 3.3V signal on the DIR side is a 5V signal on the VCC side.

OE is always grounded.

Is there something I'm missing to get this to work with SPI? Though every example I found has all the wires from one component on one side and wires from the other on the other side I have not got that setup to work.

Is there something I'm missing?

Is there something I'm missing

No matter how I connect the pins I can only get the device to translate one way.

This chip will only translate signals in one direction at any one time. It is not a bidirectional level translation chip.it has to be told the direction of the translation.

Thanks,

Got it working now