Thanks for the info on the Prop Plug and Prop Clip.·· If I incorporate the OEM components of FTDI on the PCB, then I would also like to tap the 5V USB power supply to run the BS2.·· Do you have any sucess stories to point me to, where this was done sucessfully?
Are you saying you want to run the BS2 off the 5V from the USB port? Typically this is something I would recommend against if you’ll be drawing any significant amount of current from the supply. The USB port only supplies ~100 mA to any generic device plugged into the port. If the device is a high-current device it can request up to 500 mA from the port, but the FTDI device driver does not register it as a high-current device, so the total would be ~100 mA. If your design was low-power you could tap the 5V line, however, if you are driving LEDs or anything that draws current from the pins you should factor that into total current draw (including the FTDI chip). One recommendation I would make if you’re going to embed the FTDI chip for the BS2 is to select the 5V line for VCCIO instead of the 3.3V line. Typically it wouldn’t make much difference since the I/O lines on the schematic have inline resistors on them, but it makes sense since you’re running a 5V system. The Prop Plug is configured by default for 3.3V operation. I hope this helps. Take care.
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Hate to bump an old thread, but this is the closest one I could find. I tried modifying this to work with the SX. I had a hell of a time soldering the SSOP to the adapter and fear I may have fried the chip. The USB2SER finds my BS2 in the carrier, but won't find my breadboarded SX. Is there a way to figure out if I fried the chip? What will too much heat do to the chip?
I used to solder up SOIC packages by hand all the time; SSOP is PITA!
The through-hole and SMD version of the interpreter have different pinouts. Are you sure you have them wired properly according to the type? These schematics are for the TH versions, and you can get a pinout of the SMD version by looking at the schematic to the BS2 Module itself. Does this help? Take care.
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high-techgarage said...
Hate to bump an old thread, but this is the closest one I could find. I tried modifying this to work with the SX. I had a hell of a time soldering the SSOP to the adapter and fear I may have fried the chip. The USB2SER finds my BS2 in the carrier, but won't find my breadboarded SX. Is there a way to figure out if I fried the chip? What will too much heat do to the chip?
I used to solder up SOIC packages by hand all the time; SSOP is PITA!
I've soldered quite a few of these style chips by hand and they have all worked out well. Can you post a picture of your module? It isn't completely clear how you have things setup and connected. We also need to know how it is wired up since the pinouts are different on some of the package styles.
If you were using an OEM Stamp based on the SX48 processor you could use one of my boards mentioned in the thread below to mount the chip:
Instead of using a MAX232 for programming you could just jumper across where the MAX232 is normally mounted and then connect a USB2SER where the pins come out of the board.
I am using the drawing from the Rev F SX module for the interpreter chip and the diagrams on the first page of this post. I can draw up what I have on the breadboard (or take a picture of the breadboard). The soldering is really ugly; a copper trace even pulled up off the board. I've checked for continuity between the DIP adapter board and the SSOP and all pins are connected. There are no solder bridges either. I'm fairly confident I toasted it. I'll get a schematic shortly.
Here's what my breadboard looks like now. I've tried about a thousand different combinations, but haven't gotten it yet... I'm certain the J1 programming port is the part that's mixed up. I fixed the solder bridges, but am wondering if the problems I had during soldering may have FUBARed it. Please help! I really hope this chip isn't toast...I have so many projects to do...
I didn't show it on the schematic, but my homemade cable has pin6 (DSR) and pin7 (RTS) tied together. I know the cable works because I've used it with a BS2 that I breadboarded (same for the serial to USB adapter).
What you describe are the connections for loopback. However there is no resistor providing feedback from the SIN line back to SOUT. Please refer to the original schematics posted in this thread to see what I am referring to.
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Thank you. As a note to everyone (in case I didn’t mention it above), you can also use the Prop Plug or Prop Clip in place of the USB2SER.
I noticed on the Propeller Proto Board that USB2SER is wired differently than the PropPlug. I am assuming that schematic 1 of OEM Lite should mirror these differences if I intend to use the PropPlug. I realize it is probably a very stupid question, but I just want to be certain
Thanks for your reply and it looks like nice work. However here is the circuit that I intend to make with very few modifications. I just need a very small board to drive a stepper.
I didn't show it on the schematic, but my homemade cable has pin6 (DSR) and pin7 (RTS) tied together. I know the cable works because I've used it with a BS2 that I breadboarded (same for the serial to USB adapter).
Here is a schematic from one of my old projects that used BS2 OEM. I don't remember how I came up with all of it. I must have seen it used somewhere. In particular, I don't know why I used the signal diode and the 4k7 resistor. I do know, that it worked fine... Maybe this will help you.
Comments
Are you saying you want to run the BS2 off the 5V from the USB port? Typically this is something I would recommend against if you’ll be drawing any significant amount of current from the supply. The USB port only supplies ~100 mA to any generic device plugged into the port. If the device is a high-current device it can request up to 500 mA from the port, but the FTDI device driver does not register it as a high-current device, so the total would be ~100 mA. If your design was low-power you could tap the 5V line, however, if you are driving LEDs or anything that draws current from the pins you should factor that into total current draw (including the FTDI chip). One recommendation I would make if you’re going to embed the FTDI chip for the BS2 is to select the 5V line for VCCIO instead of the 3.3V line. Typically it wouldn’t make much difference since the I/O lines on the schematic have inline resistors on them, but it makes sense since you’re running a 5V system. The Prop Plug is configured by default for 3.3V operation. I hope this helps. Take care.
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Chris Savage
Parallax Tech Support
I used to solder up SOIC packages by hand all the time; SSOP is PITA!
Thanks
The through-hole and SMD version of the interpreter have different pinouts. Are you sure you have them wired properly according to the type? These schematics are for the TH versions, and you can get a pinout of the SMD version by looking at the schematic to the BS2 Module itself. Does this help? Take care.
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Chris Savage
Parallax Engineering
I've soldered quite a few of these style chips by hand and they have all worked out well. Can you post a picture of your module? It isn't completely clear how you have things setup and connected. We also need to know how it is wired up since the pinouts are different on some of the package styles.
If you were using an OEM Stamp based on the SX48 processor you could use one of my boards mentioned in the thread below to mount the chip:
http://forums.parallax.com/forums/default.aspx?f=5&m=366382
Instead of using a MAX232 for programming you could just jumper across where the MAX232 is normally mounted and then connect a USB2SER where the pins come out of the board.
Robert
Thanks!!!
Thanks
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Chris Savage
Parallax Engineering
I'm guessing the chip is toast?
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Chris Savage
Parallax Engineering
I noticed on the Propeller Proto Board that USB2SER is wired differently than the PropPlug. I am assuming that schematic 1 of OEM Lite should mirror these differences if I intend to use the PropPlug. I realize it is probably a very stupid question, but I just want to be certain
Bruce
http://forums.parallax.com/showthread.php?127147-BASIC-Stamp-DEV-boards-based-on-OEM-chips-and-SX28-48-Protoboards
Robert
Thanks for your reply and it looks like nice work. However here is the circuit that I intend to make with very few modifications. I just need a very small board to drive a stepper.
Bruce
OMG, I just realized that my homemade BS2 cable will PERFECTLY fit a PICAXE 18M2. Is this my final test of the dark side? http://forums.parallax.com/showthread.php?125692-BYO-Board-amp-Cable&highlight=byo+board
Greg