QRST (QuasiRandom Sequence Transform
I’ve been thinking about randomness and melodic progressions recently and In addition to the probabilistic quantizer I posted, I thought I would revisit the Turing module. The Turing module produces a quasirandom sequence of bits which is translated to an output value by an 8 bit DAC and scaled to 1. I decided that I wanted more control over the range and distribution of the randomness. Like the uTuring the QRST has an adjustable 1 to 16 step shift register. The ? control sets the probability that a step will change and the width sets the maximum amount of that change. There is a minimum and maximum value for the output and a center value around which the output will cluster. The distribution control sets the width of the distribution of values around the center. At minimum the output distribution will be very narrow and at maximum the distribution will be random.
I/O
Input  Signal Range  Notes 

clock  01 gate 
the shift register moves one step with each clock 
reset  01 gate 
resets the register to 0 
Output  Signal Range  Notes 

sequencer out  minimummaximum 
range set by min and max knobs 
Controls
Control  Function  Notes 

?  sets the probability that the step will change 

steps  sets the number of steps from 116 

max  sets the maximum output value 

center  sets the center of the distribution 

min  sets the minimum output value 

width  sets the maximum change value for a step 

distribution  sets the width of the distribution form narrow to random 
Displays
Meter  Displays  Notes 

LED array  displays the current output as a percent of the total range 
Version History
Revision  File  Date  Notes 

1.0  QRST V1.0.audulus (141.5 KB)  01/21/2019  initial upload to forum 
Demos
Revision  File  Date  Notes 

1.0  QRST V1.0 demo.audulus (303.4 KB)  01/21/2019  initial upload to forum 
1.0  QRST V1.0 demo II.audulus (1.3 MB)  01/21/2019  this one’s higher CPU usage 