A BIG RED LIGHTBULB!

A while back we discussed ways to light a "BIG RED LIGHTBULB" that comes
on when one's DAW is in record. Remember? Some interest was shown in
a device that could control a lamp or two in response to MIDI Machine
Control (MMC) messages and I have coded up an 8051 program that does
just that. This program runs on my Urge To Merge (UtoM) device as may
be seen at http://home.comcast.net/~mrkesti/

The following is an excerpt from the UTOM manual.

The RelayMMC custom version was written in response to discussions
in Usenet's rec.audio.pro newsgroup and controls the relays based
on receipt of MIDI Machine Control (MMC) messages and dipswitch
settings. MIDI inputs are merged and real time messages are filtered
from MIDI input 1. The footswitch inputs are not used.

http://www.borg.com/~jglatt/tech/mmc.htm shows that MMC messages
specify device IDs and commands. The device IDs allow sub-networks
of reporting and receiving devices and the commands indicate the
current state of the reporting device.

Dipswitch DS1 specifies a 7-bit device ID and an omni mode enable.
Dipswitch DS2 specifies two 4-bit commands, one associated with
each of the two relays. The state of the relays is determined
each time a MMC message is received from either of the MIDI inputs
and the dispswitch-specified device IDs and commands are compared
with those in the messages. If the device IDs match or omni mode
is enabled, then the command values are tested. A relay is
energized when its command value matches the messages' otherwise
it is de-energized. The UTILITY lamp is lit when either relay is
energized.

The manual, shematics, and a zip of the complete source, documentation,
and tool set can be downloaded from
http://home.comcast.net/~mrkesti/downloads

THE UTOM's RELAYS MUST NEVER BE USED TO DIRECTLY SWITCH AC LINE POWER!

These relays are intended to switch low voltage circuits such as the
24-volt power typically used in tally systems. In order to safely
control AC line current, you must use the UTOM relays to control other,
more suitable, relays or solid state controls.

This program also runs on a smaller board I have designed and call the
Generic MIDI board and may better fit your application. This 3.25" by
4.0" board has only one MIDI input so it provides no merging. MMC
device ID and commands are set using jumpers on headers rather than
dipswitches. The outputs are unbuffered 8051 Port0 pins rather than
relays and will likeley require some sort of interface to control
external devices.

I have about 10 Urge To Merge units on hand and ready for almost
immediate delivery and will build Generic MIDI boards to order for
delivery in 2 to 3 weeks.

Let me know if you're interested.

Please note my fail-mail address and decode the address in my sig.

--
========================================================================
Michael Kesti | "And like, one and one don't make
| two, one and one make one."
mrkesti at comcast dot net | - The Who, Bargain
.

Relevant Pages

  • [PIC] New electronic projects site (Schematics only at the moment)
    ... currently only the schematics are posted but I will ... (iButton Door Lock) Preview, ... option in schematic to control AC, Fan & Heat) can be expanded to 6 ... relays using my Ladybug Automation Controller, ...
    (comp.arch.embedded)
  • Re: What can I replace this latching relay system with?
    ... I think you will have problems finding dimmers to use the existing control ... The relays swich this ... Centralite, LiteTouch, Vantage) mount their dimmers and switches near the ...
    (comp.home.automation)
  • Re: Freezing requirements in embedded product development
    ... begin a component performance selection table. ... This board uses 6 RF relays to select filters. ... suggested that we did not need an MCU to control the relays since the ... MCU can't directly drive the coils and the relay driver chips can be ...
    (comp.arch.embedded)
  • Re: New circuit design for home project
    ... I'd like to find somebody that could design the schematic for this. ... > One device will control the other device, with the interface between them. ... > But this device uses relays in its output. ...
    (sci.electronics.basics)