ΣSigmaStudio Ask AI Русский Log in

adau1701 gpio selected level setting

SigmaDSP & SigmaStudio hubijo Jan 17, 2014 00:00 3 replies Original on forum ↗
Subscribe
hubijo Question
Jan 17, 2014 00:00

Hi all,

I will select with two gpios (in binary mode) between 4 difference volumes. How can i realize that? i tried with demuxer, but i cant get the binary bit combination...

thanks for helping

best regards, hubijo

Audio Signal Processors

SigmaDSP Audio Processors

adau1701

KJBob Reply
Jan 17, 2014 00:00

Hello hubijo,

There's several ways to do it, one is shown below. Condition the GPIOs with buffer gates, each of which produce a selectable high bit output for a nonzero input. In the -1701 and similar DSPs with a 5.23 format, the bit positions 20, 21, and 22 provide a 1/8, 1/4, and 1/2 value respectively. Summing these provides the binary-coded result you desire.

Using the 1701 mini board, set your HW control for MP2 and MP3 to invert, then the volume increases when you press switches S3, S4, or both.

Bob

527ea3ff3ee525ed350807fd3aed1539.jpg
527ea3ff3ee525ed350807fd3aed1539.jpg
527ea3ff3ee525ed350807fd3aed1539.jpg-450x297.jpg
527ea3ff3ee525ed350807fd3aed1539.jpg-450x297.jpg
hubijo Reply
Jan 17, 2014 00:00

Hi Bob

Thanks for your answer. what do configure the DC1?

hubijo

KJBob Reply
Jan 18, 2014 00:00

Hi,

I included the DC Source DC1 to set a minimum level for when the two binary inputs are both off. Use a DC Source anywhere a constant numerical value is needed.

The DC Source block lets you choose both the numeric value of your constant and its format -- how many binary bits appear before and after the decimal point (actually the correct term here would be "binary point."). See https://ez.analog.com/docs/DOC-3168

for help with the number formats in SigmaDSP.

Bob

6607.d05573ae3e4ff5b027634395ca1d3812.jpg
6607.d05573ae3e4ff5b027634395ca1d3812.jpg
6607.d05573ae3e4ff5b027634395ca1d3812.jpg-261x142.jpg
6607.d05573ae3e4ff5b027634395ca1d3812.jpg-261x142.jpg