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Phill sug
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Joined: 24/04/2017
Location: United Kingdom
Posts: 2

Posted: 10:34pm 25 Apr 2017

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Hi
I'm a new be to this sight
I'm building a jukebox around a jukebox carousel and buttons I want to input 30+ buttons into a micromite controller I have chosen a micromite for the autorun so it will start from switch on . I'm thinking of using a 74hc165 shift register daisy chain 4 of them together for the 32+ old latch type buttons from a jukebox. I did a course
On vbasic about 10 years ago so I'm hoping it might help me. I'm after the coding for the 74hc165 in mmbasic there's plenty of of coding on the arduino but not for the micromite.
I want to input from the buttons and store them and use the selection to run the carousel. So I'm hoping that someone will have used the 74hc165 on a micromite in mmbasic or point me in the right direction.
Yours
Phill

SteveA
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Joined: 10/03/2017
Location: United Kingdom
Posts: 48

Posted: 04:47am 27 Apr 2017

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Have you considered I2C port expander IC's instead?

For example, the MCP23017 gives you 16 I/O pins. You can have up to 8 on an I2C bus, giving you 128 pins to play with. And I2C is baked into the MM, so driving them is easy!

Rgds,

Steve

matherp
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Joined: 11/12/2012
Location: United Kingdom
Posts: 8592

Posted: 05:10am 27 Apr 2017

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Quote I'm after the coding for the 74hc165 in mmbasic there's plenty of of coding on the arduino but not for the micromite.

The coding on the Micromite should be trivial. Tie all the clocks together and all the LD pins together. Tie all CLKINH pins to GND. Connect serialout to serial in across three of the chips and serialout of the 4th chip to a pin(data) on the MM

toggle LD low to load in the data. then clock out the data a bit at a time into an array

something like:

dim b%(32)
setpin LD,dout
setpin clock,dout
setpin data,din
pin(LD)=1
pin(clock)=0
do
readbits()
loop

sub readbits
local i%
pulseout LD,0.01
for i%=0 to 31
pin(clock)=1
b%(i%)=pin(data)
pin(clock)=0
next i%

CaptainBoing

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Joined: 07/09/2016
Location: United Kingdom
Posts: 1985

Posted: 05:28am 27 Apr 2017

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won't be too hard to do. Your VB will come in handy - the MMBasic primitives (i.e. the built in commands, functions and statements) have a very familiar feel to VB programmers

for your shift registers;
Take all the CE pins to GND,
Link all the PL pins together to an Output pin on the MM - hold this pin Hi normally
Link all the CP pins together to an output pin on the MM - hold this pin Hi normally
Take the Q7 pin of 3 of the 165s to the corresponding DS on the next to "cascade the data"
take the

On PL, send LO then Hi to grab your switch data

On CP, send lo then hi and sample Q7 of the highest 165. Repeat this as many times as you have switches to determine which button is pressed. Stop when you find a button pressed (unless you want to detect multiple presses)

Code might look like this:

CONST PL=1, CP=2, Q7=3 ' change these to whatever pin numbers you use

DIM Switches AS INTEGER ' variable to hold the switch status as a bit array
DIM n AS INTEGER ' counter for your loop

SETPIN PL,DOUT
SETPIN CP,DOUT
SETPIN Q7,DIN

PIN (PL)=1
PIN (CP)=1

' this is the point you capture the switch data
Switches=0 ' clear any old data
PULSE PL,1 ' 1mS pulse to grab switches

FOR n=31 TO 0 STEP -1 ' change 31 to 29 if you only want 30 switches
Switches=(Switches<<1) + PIN(Q7) ' gradually build switch status in variable
PULSE CP,1' shift next bit
NEXT

' here Switches has a bit array of the switches that were pressed

probably more to it than this simple "thinks" but should be enough to get you going.

hth

CaptainBoing

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Joined: 07/09/2016
Location: United Kingdom
Posts: 1985

Posted: 05:32am 27 Apr 2017

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sorry Peter, not competing I evidently took 18 minutes to type that in

Phill sug
Newbie

Joined: 24/04/2017
Location: United Kingdom
Posts: 2

Posted: 08:47pm 29 Apr 2017

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Thanks for the response just going on holiday so wil have a look when I get back
Thank
Phill

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