I am finding different ways of solving a wiring problem and am toying with shift registers.
I have succeeded in connecting a number of 4021's and 595's to make a 16 (or more) switch to led connection using 3 wires
see http://forum.arduino.cc/index.php?topic=208794.msg1540077#msg1540077
I am now wondering if I could do the same with a pipo shift register such as the 74XX322.
I can't get the answers I want from the info I have found and wonder if someone would mind helping me with answers or pointing me to a publication that would help.
Can I wire up the 322 to an arduino and run it in the same way | am doing with the 4021 and 595 to get input and output? i.e. put one at each end so I can get switches and lights to work at both ends?
Would it be able to do this both ways at the same time? I suppose in actuality it is not doing it all at the same time with the 4021 and 595 but it acts as if it is and looks that way, the switches are not high speed so a delay of , say, 1 second won't matter.
I have added a picture of the pins of a 322.
Might there be a better chip to look at? I know the 74xx95 and 96 are not available any more but I really only need 4 bit info and not eight.
Yup, the '299 is about the most flexible 8-bit shift register there is, synchronous shifts or
loads, separate output enable, shifts either direction...
thanks, I have been looking at the 229. Is it at all easy to program the arduino to allow me to have two of them receiving info from switches, sending the info serially to an arduino and sending the output from one to be read as parallel output on the other and vice versa to supply leds at both ends similar to my project in the above link?
I am just guessing here but would the operation go something like this.
put s0 and s1 high to put the chip in piso.
turn oe1 high to read pins i/o 0-7
turn oe1 low and send the info on every clock pulse to the arduino out of ds0
put so high and s1 low to give me shift right sipo
send data back up ds0 on every clock pulse
turn oe1 high to write it on i/o 0-7
repeat.
?????????
Should this now be transferred to 'arduino programming'?
It's also common to use the 595(output) in combination with the 166(input) sharing the same control bus (data/clock/latch) thus keeping the directional parts separate.
yea , thanks Mark it is the 299 I want.
For some reason I went back to the 332? The drawing at the bottom of thread is a 299 so it is that I want and not a 229 or even a 332.
Pwillaird, I am using a 4021 and a 595 at present but would like to, just for the shear hell of it, run the project with one chip at each end.
