Bluetooth for BasicX 24 and 35 serial communications

Started by flyerx_2000 February 6, 2013
Hello,

I would like to monitor the output of a BasicX24 and 35 using a stand-alone external Bluetooth device connected to a 9-pin serial port. This serial port is connected to the serial pins on the BasicX. I have found many of these devices online but, since the BasicX does not use the standard RS232 voltage levels, is there a Bluetooth device that can reliably work with the BasicX? I only need it one way communications: from processor to computer. Computer will be running Windows 7.

Thanks for any info on this.

FlyerX

> ... is there a Bluetooth device that can reliably work with the BasicX?

You'll need a Bluetooth module that will accept and produce inverted TTL
logic. I suspect that shopping Sparkfun and similar sites will find
some options but, if not, you can build your own.

Some time ago I designed a small circuit board that I've used in many
projects, which adapts an ESD200 module to the standard four-pin (plus
one for power) Com1 port pinout of the BX-24 and similar processors. A
five-pin header alongside BX-24 pins 1 through 4 allows plugging a wired
RS232-ish serial connection, the Bluetooth module, or a modified
Parallax PropPlug FTDI USB/serial adapter.

I'll be surprised if you can't find something off the shelf today but,
if you need it, I'll post the schematic and an image or two of what I built.

Tom

Thanks for your answer. I failed to mention that the BX35 has the hex inverter as described in its application notes. The BX24 does not need to be inverted.

Both chips can communicate with a computer perfectly but I was concerned about the lower and non-standard (0-5V) voltage levels of the BX serial port.

I can put a MAX chip on the serial output and make the BasicX have an standard RS232 output. But it would be great if I could find an off-the-shelf bluetooth device that is as forgiving as the PC port with the voltage levels.

FlyerX

--- In b..., Tom Becker wrote:
>
> > ... is there a Bluetooth device that can reliably work with the BasicX?
>
> You'll need a Bluetooth module that will accept and produce inverted TTL
> logic. I suspect that shopping Sparkfun and similar sites will find
> some options but, if not, you can build your own.
>
> Some time ago I designed a small circuit board that I've used in many
> projects, which adapts an ESD200 module to the standard four-pin (plus
> one for power) Com1 port pinout of the BX-24 and similar processors. A
> five-pin header alongside BX-24 pins 1 through 4 allows plugging a wired
> RS232-ish serial connection, the Bluetooth module, or a modified
> Parallax PropPlug FTDI USB/serial adapter.
>
> I'll be surprised if you can't find something off the shelf today but,
> if you need it, I'll post the schematic and an image or two of what I built.
>
> Tom
>

Flyer,
I use an AirCable Serial 5x with a PicStick3 running on 5v. levels.
I think I have also used it with the BX-24 but that was a while back.

A great little device for sending data to my cell phone.

http://www.aircable.net/products/serial5x.php

Ian
--- In b..., "flyerx_2000" wrote:
>
> Thanks for your answer. I failed to mention that the BX35 has the hex inverter as described in its application notes. The BX24 does not need to be inverted.
>
> Both chips can communicate with a computer perfectly but I was concerned about the lower and non-standard (0-5V) voltage levels of the BX serial port.
>
> I can put a MAX chip on the serial output and make the BasicX have an standard RS232 output. But it would be great if I could find an off-the-shelf bluetooth device that is as forgiving as the PC port with the voltage levels.
>
> FlyerX
>
> --- In b..., Tom Becker wrote:
> >
> > > ... is there a Bluetooth device that can reliably work with the BasicX?
> >
> > You'll need a Bluetooth module that will accept and produce inverted TTL
> > logic. I suspect that shopping Sparkfun and similar sites will find
> > some options but, if not, you can build your own.
> >
> > Some time ago I designed a small circuit board that I've used in many
> > projects, which adapts an ESD200 module to the standard four-pin (plus
> > one for power) Com1 port pinout of the BX-24 and similar processors. A
> > five-pin header alongside BX-24 pins 1 through 4 allows plugging a wired
> > RS232-ish serial connection, the Bluetooth module, or a modified
> > Parallax PropPlug FTDI USB/serial adapter.
> >
> > I'll be surprised if you can't find something off the shelf today but,
> > if you need it, I'll post the schematic and an image or two of what I built.
> >
> > Tom
>