Hardware for SEQ 3? led/button array?

[intellijel]

I haven't built a version of the SEQ yet but I plan to build V3 with the LED/BUtton matrix.

I have already ordered an array of buttons+PCBs from SparkFun in anticipation.

I assume the rest of the project will use all of the same hardware as the older SEQ except that there are some restricted options (e.g. Only 2x40 LCDs will be supported).

Anything else I need (e.g. other stuff to go with the button/led matrix)??? e.g. MAX7221 led driver

I would like to offer my services to beta test it if I can get the hardware together quickly.

cheers,

      intellijel

[TK.]

Hi intellijel,

yes, MBSEQ V3 doesn't require more buttons/LEDs than MBSEQ V2. But if you design a new frontpanel, please consider the following:

- you could add 4 additional buttons and LEDs for switching between the 4 track groups (track 1-4, 5-8, 9-12, 13-16). Without these buttons/LEDs, you have to cycle between the groups with F4. The group number will be display at the LCD (most menu pages)

- you could add 3 additional buttons/LEDs for switching between the assignable trigger layers. Without these buttons/LEds, you have to use F3 in order to cycle between the layers, the selected layer will only be displayed within the EDIT screen

64 button/Duo-LED matrix: sorry, there are no schematics yet (lack of time... :-( ) - I will try to draw them next week. It uses 2 x 74HC165 and 4 x 74HC595, no special chips

Best Regards, Thorsten.

[intellijel]

cool, thanks TK!

Checkout this led matrix driver chip: maxim MAX7221

Could make things easier for your design.

I'll be building this sequencer over the next few weeks.

thanks!

[TK.]

Hi,

normaly I avoid the use of special chips for MBHP, because they increase the complexity and the support effort. In addition, everything which can only be purchased from a small number of distributors should be avoided, since this increases the shipping costs and ordering effort.

Best example is the MAX525 - many people suggested this chip years ago, finally I put this into the MBHP, but at the end there is only a small number of people who really built the module (due to the high costs), and we still have no "cheap&simple" solution for a CV converter (assumed that the MBHP_AOUT_LC is only for freaks with enough endurance for soldering so many resistors).

To the MAX7221: it's a nice chip, but temporary not available at Reichelt, which could mean, that Maxim is going to discontinue it. Unfortunately this happens very often... :-/

Best Regards, Thorsten.