Clearing a 595 bit shift register on startup

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1

I have a 74HC595 8-bit shift register. When I shutdown Arduino with some pins set to high on the 595, on the next startup they are still on until I clear them in the setup functions in the program. This causes the leds connected to the register to flash.

How do I clear the 595? I have tried setting the clear pin (SCLR) low trough a pull down resistor and in the code turn it high again. So I have connected the SCLR pin both to ground (through a 10 k resistor) and to Arduino.

2

I don't think the outputs actually clear until the RCKL is clocked low to high when MCLR is low.
If you need the outputs low until you can make that happen in the sketch, then use a pullup on OE/ and pulldown resistors on the outputs.

3

The 74HC595 has a pin labelled "OE"...