Can't Seem to TX to uMP3

[Zombie-F]

As I recall, the only settings on the uMP3 I need to change to get it to communicate with the Prop-1 is to set the Baud to 2400 and to set the delay response to 5 ms.  I have the latest non-beta firmware installed on the uMP3 and have changed the settings using the uMP3 configuration tool.

For some reason, my Transmitted commands aren't being received by the uMP3.  I have determined this by doing the following:

• Reset the uMP3 config and re-sent the baud and delay response changes.
• Removed the ULN2803 just to eliminate it as a potential communication problem.
• Sent commands to the uMP3 via a usb2ser and using the uMP3 config tool.  All commands sent and received worked normally.
• I have ohmed out all of my cables to ensure there are no intermittent connections.
• I am able to receive the ">" transmitted by the uMP3 after it starts up.  However, if I reset my prop-1, it just waits forever to receive another ">" from the uMP3... which to me is a sign that the trasmitted carriage return isn't getting to the uMP3.

I have tried all of this on two prop-1s and two uMP3 boards to ensure I don't have any defective boards.

Is there something wrong with my code or is there some other setting in the uMP3 config that could be incorrect?

Here's the code I wrote to just play a single file:

Code Select Expand


' {$STAMP BS1}
' {$PBASIC 1.0}

' -----[ I/O Definitions ]-------------------------------------------------
SYMBOL  TX              = 6                     ' to UMP3.R; no ULN
SYMBOL  RX              = 5                     ' to UMP3.T; no ULN

' -----[ Constants ]-------------------------------------------------------
SYMBOL  Baud            = OT2400

' -----[ Variables ]-------------------------------------------------------
SYMBOL  char            = B2                    ' character value

' -----[ EEPROM Data ]-----------------------------------------------------


' -----[ Initialization ]--------------------------------------------------
  PAUSE 5000                                    ' let uMP3 start

Prod_uMP3:
  SEROUT TX, Baud, (13)                         ' send CR
  SERIN  RX, Baud, char                         ' get response
  DEBUG CR, char
  IF char <> ">" THEN Prod_uMP3                 ' wait for ">"

' -----[ Program Code ]----------------------------------------------------
SEROUT TX, baud, ("PC F /gr1.mp3", 13)
DEBUG "Should be playing sound"


Here's a photo of my connections.  The Tx pin on the prop-1 goes to Rx on the uMP3 and the Rx pin on the prop-1 goes to Tx on the uMP3.

[Zombie-F]

Also, here is a screen shot of my current uMP3 configuration.  I suspect I have something wrong here but I can't figure out what.

[JonnyMac]

Based on the photo it looks like you've got the TX line out of the Prop-1 on P5, not on P6 where you code states it should be.  I tend to use P7 and P6 for the uMP3.  Make sure that if you're using either P6 or P7 (or both) that the associated SETUP jumper is in the UP position) -- yours look to be DN.

[Zombie-F]

Thank you for the help.

About the photo... what you're seeing is P7's reflection against the connector.  They actually are on P6 and P5 it just looks deceiving because of the reflection from the flash.  :p

It was the jumper that was causing me problems.  I don't know why it didn't occur to me that I had the jumper wrong.  *slaps own head*

P7 is set aside for a Ping))) sensor.  :)