I am having trouble with BS2pe OEM that I have built.· Please see the attached bit map for the layout.· When I connect to the Stamp Editor I get an echo but no loopback and "No BASIC Stamps found".
-- check power supply, on all chips.
-- check soldering under a microscope
-- check for RST/ and TX and RX activity right at the Stamp pins. ('scope if available)
-- check for voltage levels on the eeprom.
-- be sure your SX48 is really programmed as a BS2pe. (not a 'p for example)
I have just spent the day testing the board with a scope and comparing it to a BS2pe module.
1. there is RST/, TX and RX activity at the SX48 pins
2. the noise on the 5V rail is +/- 40 mV ripple
3. the eeprom levels are at 5 V but there is some noise on both the SCL and SDA pins
So, do you think that the noise on the 5V rail could be the cause of the problem? The 5V reg is LT1762.
Also check the crystal pins for oscillation. On a voltmeter, OSC2 (pin 3 on the SX48) should be at approximatly 2.5 volts. On a 'scope with a 10x probe, you should see a squarish wave with a period of 12.5 ns.
Is there activity on the eeprom lines, conincidental with the activity on tx and rx?
Again, check the soldering on the SX48, especially to pins 1 to 9. If it was hand soldered, it is awfully easy to have an fatal open or shorted connection.
Definatly go to the Parallax web site and download 2.2.5. I spent hours trying to figure out why a BS2 ran a program just fine and all I got from the BS2pe was "could not find stamp". All of my books suggested that both the stamps will run on the version I had but obviously there has been a change in the newer manufactured stamps. Chris Savage sugested the update and I have since had a happy stamp.
Randy
P.S. to the Parallax guys if you read the replies, I Don't know how long ago you made the change in the stamp but you might consider a note in the stamps packaging concerning what version of software is needed.
That is a possibility. Version 1.2 BS2pe's work fine with the older version 2.2 IDE. However, the latest public BS2pe firmware is version 1.4 (It deals with a bug in DTMF frequencies). I had a support call yesterday regarding the same issue, that the new BS2pe v 1.4 was recognized only by the version 2.25 IDE now available on the Parallax web site. There was also an issue with our Stache microprogrammer in relation to the new IDE that we are going to have to resolve.
Comments
Dave
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Dave Andreae
Tech Support
dandreae@parallax.com
Http://www.parallax.com
·
-- check power supply, on all chips.
-- check soldering under a microscope
-- check for RST/ and TX and RX activity right at the Stamp pins. ('scope if available)
-- check for voltage levels on the eeprom.
-- be sure your SX48 is really programmed as a BS2pe. (not a 'p for example)
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Tracy Allen
www.emesystems.com
1. there is RST/, TX and RX activity at the SX48 pins
2. the noise on the 5V rail is +/- 40 mV ripple
3. the eeprom levels are at 5 V but there is some noise on both the SCL and SDA pins
So, do you think that the noise on the 5V rail could be the cause of the problem? The 5V reg is LT1762.
Cheers,
Helen
Also check the crystal pins for oscillation. On a voltmeter, OSC2 (pin 3 on the SX48) should be at approximatly 2.5 volts. On a 'scope with a 10x probe, you should see a squarish wave with a period of 12.5 ns.
Is there activity on the eeprom lines, conincidental with the activity on tx and rx?
Again, check the soldering on the SX48, especially to pins 1 to 9. If it was hand soldered, it is awfully easy to have an fatal open or shorted connection.
Good luck. I'm sure you will resolve the problem.
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Tracy Allen
www.emesystems.com
Don Nilles
Definatly go to the Parallax web site and download 2.2.5. I spent hours trying to figure out why a BS2 ran a program just fine and all I got from the BS2pe was "could not find stamp". All of my books suggested that both the stamps will run on the version I had but obviously there has been a change in the newer manufactured stamps. Chris Savage sugested the update and I have since had a happy stamp.
Randy
P.S. to the Parallax guys if you read the replies, I Don't know how long ago you made the change in the stamp but you might consider a note in the stamps packaging concerning what version of software is needed.
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Tracy Allen
www.emesystems.com