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computer guy
04-23-2008, 08:33 AM
I have a "matchport b/g" connected to a propeller and they will not communicate.

The propeller is running FullDuplexSerial and I have tried all of the modes (0-3) and it is set for 9600 baud.

The "matchport b/g" is configured for the following.

RS232
8 bits
1 stop bit
no flow control
9600 baud

Using my Parallax USB Oscilloscope I have determined that they are going from (logic level) high to low fine. (3.3v to 1.7v aprox)

I can get both devices to talk to the PC via a prop plug but not to each other.

Does anyone know what might cause this?


Thank you http://forums.parallax.com/images/smilies/smile.gif

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Post Edited (computer guy) : 4/23/2008 3:20:59 AM GMT

Mike Green
04-23-2008, 08:52 AM
Perhaps you have receive and transmit backwards? The first pin number in FullDuplexSerial.start is the receive pin # (from the MatchPort) and the second pin number is the transmit pin # (to the MatchPort).

Logic low should be lower than 1.7V. That may be a sign that you have things reversed.

Bob Lawrence (VE1RLL)
04-23-2008, 08:53 AM
Is this the hookup you are using?

================================================== ===========

Serial Interfaces
The MatchPort b/g serial interface is 3.3V logic level and typically connected to a
Universal Asynchronous Receiver/Transmitter (UART). For connection to an external
device, the demo board has RS-232/422/485 transceivers. CON1 and CON2 support
RS-232/485. Connect to a PC using a null-modem serial cable with 9-pin connectors
(F/F).
The table below lists the RS-232 signals and corresponding pins on the MatchPort
b/g. All signals are level-shifted by the RS-232 transceivers

Table 3-1. RS-232 Signals
MatchPort b/g
PIN FUNCTION
DB9
Pin #
UART x Conx

http://www.lantronix.com/pdf/MatchPort_IG.pdf
TXDx (Data Out) 3
RXDx (Data In) 2
CTSx (HW Flow Control Input) 8
RTSx (HW Flow Control Output) 7
DCDx (Modem Control Input) 1
DTRx (Modem Control Output) 4

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Aka: CosmicBob

computer guy
04-23-2008, 09:22 AM
I have checked the pins and am sure that they are around the right way.

I have the following connections.

----------------------------------------------------------------
Matchport **** PropPlug

TX ---------> RX
RX <--------- TX
GND <-----> GND

OR

Prop **** PropPlug

TX(P26) ----> RX
RX(P27) <---- TX
GND <------> GND

OR

Matchport **** Prop

TX ---------> RX(P27)
RX <--------- TX(P26)
GND <-----> GND


*Doesn't work
*Works
--------------------------------------------------------------------

Thank you http://forums.parallax.com/images/smilies/smile.gif

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Check out my robot using the propeller RECONAUTOR (http://robot.tmcp.com.au)
If you like my avatar then check this out Propeller Domed Stickers for sale (http://forums.parallax.com/showthread.php?p=701193)

Building Blocks To The Propeller Chip (http://robot.tmcp.com.au/buildingblock)

Post Edited (computer guy) : 4/23/2008 2:28:20 AM GMT

computer guy
04-23-2008, 10:18 AM
Some of you may not get this. http://forums.parallax.com/images/smilies/smile.gif

I wound the window down and up a few times and now it works.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Check out my robot using the propeller RECONAUTOR (http://robot.tmcp.com.au)
If you like my avatar then check this out Propeller Domed Stickers for sale (http://forums.parallax.com/showthread.php?p=701193)

Building Blocks To The Propeller Chip (http://robot.tmcp.com.au/buildingblock)

Jesse Druehl
04-23-2008, 11:10 AM
braypp terminal?

Jesse
W5JCD

computer guy
04-23-2008, 12:00 PM
Jesse,

Assuming you are asking if I am using braypp terminal.
I use Putty or Hyper Terminal for serial coms. http://forums.parallax.com/images/smilies/smile.gif

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Check out my robot using the propeller RECONAUTOR (http://robot.tmcp.com.au)
If you like my avatar then check this out Propeller Domed Stickers for sale (http://forums.parallax.com/showthread.php?p=701193)

Building Blocks To The Propeller Chip (http://robot.tmcp.com.au/buildingblock)

Post Edited (computer guy) : 4/23/2008 5:38:06 AM GMT