--- In o...@yahoogroups.com, "design.wonk" wrote:
>
> Greetings,
>
> I have an ooPIC-R that I am planning to use to control an audio
> installation. The ooPIC will be used to drive a Daisy MP3 player
(kit
> from Make magazine). I am familiar with RS232C types of serial
> connections, but this type of serial IO is new to me. The Daisy
has a
> serial control interface with TX and RX pins. I will be providing
> power to the Daisy using one of the regulated connections on the
ooPIC.
>
> This is the diagram of the serial pins on the target device.
> My question is how do I wire these two boards together. The
grounds
> should be linked by the power configuration, but how many other
wires
> are needed? Which ooPIC objects should I be using? I am just not
sure
> about timing and flow control.
>
> thanks
>
> -Ray

>From the schematic, the device doesn't offer flow control. If the
OOPic has to RECEIVE information from the device and the messages are
more than about 4 chars at almost any slow baud rate, this project
ain't happening. We've been talking about this almost continuously
for the last two weeks.

Unfortunately, the OOPic R has an RS232 level shifter built in.
Also, unfortunately, it isn't real RS232. Probably the easiest thing
to do is shift the levels of your device and plug it into the OOPic
DB-9 connector. Use a level shifter like
http://www.pololu.com/catalog/product/126 Connect the device Rx line
to the level shifter Tx and vice versa. You can ignore the other
signals but you do need to provide power and common ground.

Now, since the OOPic has a female connector and the level shifter
also has a female connector, you need a male-by-male null modem to
make the connection. See http://www.cablesforless.com/index.asp?
PageAction=VIEWCATS&Category=428 Use oSerialPort

If the OOPic really doesn't need to receive anything, you can use
oSerialL and just connect the OOPic output pin (pick one) to the
device Rx line.

Richard



(You need to be a member of oopic -- send a blank email to oopic-subscribe@yahoogroups.com )

--- In o...@yahoogroups.com, "rtstofer" wrote:
>
> --- In o...@yahoogroups.com, "design.wonk" wrote:
> >
> > Greetings,
> >
> > I have an ooPIC-R that I am planning to use to control an audio
> > installation. The ooPIC will be used to drive a Daisy MP3 player
> (kit
> > from Make magazine). I am familiar with RS232C types of serial
> > connections, but this type of serial IO is new to me. The Daisy
> has a
> > serial control interface with TX and RX pins. I will be providing
> > power to the Daisy using one of the regulated connections on the
> ooPIC.
> >
> > This is the diagram of the serial pins on the target device.
> >
> >
> > My question is how do I wire these two boards together. The
> grounds
> > should be linked by the power configuration, but how many other
> wires
> > are needed? Which ooPIC objects should I be using? I am just not
> sure
> > about timing and flow control.
> >
> > thanks
> >
> > -Ray
>
> From the schematic, the device doesn't offer flow control. If the
> OOPic has to RECEIVE information from the device and the messages are
> more than about 4 chars at almost any slow baud rate, this project
> ain't happening. We've been talking about this almost continuously
> for the last two weeks.
>
> Unfortunately, the OOPic R has an RS232 level shifter built in.
> Also, unfortunately, it isn't real RS232. Probably the easiest thing
> to do is shift the levels of your device and plug it into the OOPic
> DB-9 connector. Use a level shifter like
> http://www.pololu.com/catalog/product/126 Connect the device Rx line
> to the level shifter Tx and vice versa. You can ignore the other
> signals but you do need to provide power and common ground.
>
> Now, since the OOPic has a female connector and the level shifter
> also has a female connector, you need a male-by-male null modem to
> make the connection. See http://www.cablesforless.com/index.asp?
> PageAction=VIEWCATS&Category=428 Use oSerialPort
>
> If the OOPic really doesn't need to receive anything, you can use
> oSerialL and just connect the OOPic output pin (pick one) to the
> device Rx line.
>
> Richard
>

Richard,

Thanks for the information. The ooPIC does not need to receive
any information from the mp3 device and will be sending 2 char
commands, so it looks like I am OK with the oSerialL. Regarding
linking the grounds - if I am providing power to the mp3 device from
the ooPIC-R do I need to do anything else to have a common ground?

thanks

-Ray



(You need to be a member of oopic -- send a blank email to oopic-subscribe@yahoogroups.com )

> Richard,
>
> Thanks for the information. The ooPIC does not need to receive
> any information from the mp3 device and will be sending 2 char
> commands, so it looks like I am OK with the oSerialL. Regarding
> linking the grounds - if I am providing power to the mp3 device from
> the ooPIC-R do I need to do anything else to have a common ground?
>
> thanks
>
> -Ray
>

No, the common power supply will provide common ground.

Richard



(You need to be a member of oopic -- send a blank email to oopic-subscribe@yahoogroups.com )