Is it possible to interface with 2000 era System Monitor

[src]

My new boat (2000 310 Sundancer w/twin 7.4) has this System Monitor panel:


Since it's a 3 wire interface, that makes me think that it might be using a standard communication protocol. I was wondering if any of the stock systems are transmitting NMEA, or similar, codes that can be used up by other equipment. My initial impression is that it's unlikely, but I figured I'd ask just in case.

I'm just trying to plot out my electronics upgrades/modifications, and would like to know what is and isn't possible with the stock systems. Thanks!

 

[Four Suns]

I will start by saying I have not touched any of this so this my "educated guess." Without the education. Other than having to troubleshoot my system and replacing the coax connectors and fixing the ground wire.

I would guess that is a serial connection. There is a box somewhere else on the boat that is the actual embedded computer collecting data from sensors and it probably has a serial output going to the display (mine is on a bulkhead in the engineroom by the battery charger). There are two possibilities... one is that there is an embedded processor in that display and it is getting the NMEA sentences over that serial line and processing them and lighting up the LED's (I think this is unlikely) or that is a serial connection and it's just setting a Hi or Lo bit (or voltage) on the pins that light up the respective LED's.

You can hook up the connector to a serial port and display/record what the box (located somewhere else on the boat) is putting out. You may want to find that box and see if it has another serial connector on it that is putting out data and plug into that if it exists.

The NMEA sentence strings can be manipulated. A lot of the NMEA strings that thing would use are probably obsolete or custom (see http://gpsd.berlios.de/NMEA.txt ) but there are multiplexers out there (Brookstone, ActiSense) that allow you to reformat values and strings on the listener side of a box and transmit them out the talker side of the box. You could then feed them into an NMEA 2000 translater.

This is something I've been contemplating with my Sea Ray Monitor (a newer version of what you have) and take advantage of all the wiring already on the boat... I'll be starting with a optically isolated serial connector plugged into my MacBook and stick it on connectors just to find out what it all does.

 

[kaz911]

Get a cheap protocol decoder. I doubt it is nmea - but possibly some kind of proprietary Serial protocol.

If the back is not potted - look at the receiver chip and look it up if you can find the part number on it.

I would guess it is just a "byte" sized multiplexed integer (possible values 0-255) and any value sets an LED. 12 on/off values - so 144 combinations needed to be able to turn each on/off individually. If they have been really lazy - it is just two "bytes" - (16 bit) - and each bit can be turned on / off - and 1 bit = 1 led.

 

[LTD.330]

Hey src, what did you find out? I have the same System Monitor and like the idea of swapping it out for something that provides more information.

 

[src]

I've not found any more information on the system, and haven't had a lot of free time to look at it due to higher priority items. I might pull the display panel off this weekend just to look at the cable, since that would tell me a lot (2 or 3 wires = logic processing somewhere, more wires = dumb sensors).

 

[tdschafer]

There is another "box" to this system as Gary stated. Mine is mounted under my dash. My system monitor has been inoperable since I purchased my boat. I would love to get more (any really) info on my systems while underway! The thing that concerns me is that I have no warning buzzers now. Therefore, if I am on an extended cruise I have to be very diligent about visually monitoring my gauges. In addition, there are things like the bilge pumps & transmission temp that cannot be monitored by the instrumentation.
I recently contacted Sea Ray about converting this system & they said there are two parts that have superseded the originals ( to replace the box & display) but the plug configuration doesn't appear correct. I need to open the dash & check it again. Oh yeah, and the parts were just shy of $1500, so I want to make sure that I can use them before I purchase them!

Todd


Sent from my iPhone using Tapatalk
Todd