This is really a question rather than a tip but is there any plans to discontinue the PPDB? The reason I ask is that it's been on sale for a very long time. Seems that Parallax may be eliminating inventory.
This is really a question rather than a tip but is there any plans to discontinue the PPDB? The reason I ask is that it's been on sale for a very long time. Seems that Parallax may be eliminating inventory.
I believe the stock went down to zero, and they did another run. I don't speak for them, but it looks like a good seller, as they have sold plenty in the last two weeks.
So I got scared about the ppdb being discontinued I went out and bought two more. I hope that the board continues to live on but I'm ready for the worst! To be far though I normally just put the propeller onto a breadboard and go from there. In the end there are very few part to make a propeller work!
I love the board also but was actually hoping it would be discontinued for a new version. Something with maybe an LCD instead of the 16-segment LED's. With something other than the 9-pin serial port. And also allowing it to be powered via USB. And use a switching regulator for the 5v supply. I've been planning to mod mine and have done some of the above things, but it's not as clean and neat as it used to be.
How about an XBee socket instead of the 16-segment LEDs? XBees are becoming very popular these days, and many of Parallax's other boards have XBee sockets. I don't think an on-board LCD would be a good choice because an external one can be added very easily, and because not everyone will need an on-board LCD and might not want to pay for it (I wouldn't want to).
Good luck powering such a big board off of USB - USB can only supply 0.5A, but the PPDB can use up to 1A (but I have no idea how much it uses normally without much stuff on it).
I've powered the board via USB and for debugging code with a couple sensors and LEDs it's no problem. It adds convenience when I'm trying out an idea and a wall socket isn't near by.
I had my eye on this board for some time and when it dropped in price I had to grab one. It's a great dev board with a ton of options. I too like the idea of adding an LCD or even an OLED vs the 7-seg displays but it is still great as is.
The RS-232/Max section of the board is the least utilized for me. I would not be too sad to see that go. Not sure how much longer the PS/2 jacks are going to be relevant. I use them, but would not be sad to see them replaced with something else in the next revision.
In My Opinion
1. My copy of the PPDB has two 20-pin strips for the prop DIP instead of a socket. Because one or both strips be very slightly rotated, the spacing was not exactly 600 mils. After curling pins on two different prop DIPs, I finally was able to plug in an Augat socket which has much stiffer pins and plugged the prop chip into that. Using a proper socket would be better.
2. SIX digits of SEVENTEEN-segment LEDs for a 32-bit machine???
3. The DS1302 is really pretty obsolete.
4. I have no use at all for RS-232 or the PS-2 stuff. Or VGA.
5. Would like to have an XBee socket. Also Micro-SD.
In My Opinion
1. My copy of the PPDB has two 20-pin strips for the prop DIP instead of a socket. Because one or both strips be very slightly rotated, the spacing was not exactly 600 mils. After curling pins on two different prop DIPs, I finally was able to plug in an Augat socket which has much stiffer pins and plugged the prop chip into that. Using a proper socket would be better.
2. SIX digits of SEVENTEEN-segment LEDs for a 32-bit machine???
3. The DS1302 is really pretty obsolete.
4. I have no use at all for RS-232 or the PS-2 stuff. Or VGA.
5. Would like to have an XBee socket. Also Micro-SD.
I had the same problem getting the prop plugged in on my first PPDB. After several tries at "unmangling" the pins I finally got it more or less plugged into the sockets. There are a couple of pins that are all bented up and not actually in the socket but are making contact with the metal part with enough force to make a connection (reliable?). I'm not sure why Parallax went that route instead of an actual socket. The prop plugged into my "spare" PPDB fine.
Back in the day when the PPDB was designed. It was meant to be backward compatible as well as forward compatible. VGA was all there was...no DVI, HDMI, etc. If it didn't have a serial port at the time, I wouldn't have ever purchased one(PPDB). RS232 was way more reliable then the early usb 2.0 when talking to stuff you've hacked into like a toaster oven or a Video camera remote control.
'
If you look at were the market was back in the day, You would understand.
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I'm not sure what Parallax was thinking with the socket either. Most new kids can't change a flat tire let alone insert a 40 pin chip into a socket.
On the peripheral mix, the 17-segment LED's are a strange choice. Nobody is going to use those in a final project because they eat too many pins.
Serial is a necessity. It's still the go-to standard for low powered device comms. Adapters are more of a problem on the PC end because Windows 7 and 8 killed a lot of the cheap ones but there are still a LOT of legacy RS232 devices, especially in industry.
PS/2 is going to be your standard for full-size keyboards. The Prop can't practically do USB, and most USB keyboards will speak PS/2 with a passive adapter. Most industrial hardened keyboards are available in PS/2, and cheap PS/2 keyboards are readily available through eBay. As for a mouse, I don't really see the need for a mouse on practical prop projects, since it can't support a true high resolution bitmap display.
Similarly, VGA is going to be your standard for video. The Prop can't do HDMI and for about $50 you can get a VGA to HDMI adapter. A few years ago I'd have wondered why no NTSC but that turned out to be prescient.
Pots, switches, and blinky LED's are always good. A SD socket would be good. Pre-wired delta sigma ADC would be nice but possibly hard with a DIP prop and the large layout. Ethernet is a bit fluid, and it's probably not worth the price hit to stick something on the PPDB that might not be favored later; remember when it was all ENC28J60? (Still is for me, but I can stick a < $20 adapter in the protoboard easily enough.) It's already got servo headers, right? How about a cheap H-bridge for linear and bipolar stepper motors?
And I'm updating it too, no wires just plug it in it and it connects to P0, Gnd and Power(you can still use P0 if you don't need the LEDs)
Uses a single IC buffer (SN74LV1T34DBVR) that runs on either 3.3v or 5v with a 2v in as a high state, and the rest is already 3.3v and 5v compatible so it does not matter what your upper power rail is.
It also have 4 holes as to not completely block access to the power rails underneath, so you can push 2 pairs of jumper wires down.
Available in 1-2weeks. will give schematic in case you want to use it in final product.
That's nice, but it's not a reasonable part of a general-purpose development system, when you can find so many LCD displays that givey you 16 alphanumeric digits and don't need a driver. I strongly suspect the LED's were kind of "showing off" because yeah, the Propeller can drive them, even though it's a big waste of the pins to CPU ratio to do so. The PPDB is a bout prototyping, which is about building things you might later want to remake as a permanent project. The 17-segment LED's are cool but they just don't belong on that platform. Nobody is going to source the LED's and drivers when there are so many cheaper solutions much more readily available.
17Seg cost around $1 each, so $6 plus $4 in driver parts =$10
But seg led's is kind of old school and I have not seen any new commercial products using it.
It scrolls the text to badly.
The PPDB does need a complete overhaul, with 3" LCD and Bluetooth etc
I'm not sure what Parallax was thinking with the socket either. Most new kids can't change a flat tire let alone insert a 40 pin chip into a socket.
Without a socket, if you fry your prop you lose a $150 board. With a socket, you only lose one $8 chip. You can ruin the pins of 18 props trying to get one into the socket and a socket will still be worth it. Also, it says "professional" on the tin - that implies that its typical intended user knows how to get a chip into a socket (although I would still recommend the board to beginners).
But my point is that with 16 segments (not counting the DP) these can be easily wired to shift registers, much like 7-segment displays are often wired and taking only 3 I/O pins regardless of how many digits you have. The caveat is you lose the DP. With a 7-segment display you usually have that extra bit available for the DP.
At the time the board was designed there was a common interface chip that was like the 16-segment version of the MAX7219. I haven't looked for it lately, however the big thing at the time was to let the Propeller multiplex the displays using shift registers.
The same argument (I/O pin count) can be used with dot-matrix displays, but the solution is similar. Multiplex to reduce overall I/O pin count.
And I'm updating it too, no wires just plug it in it and it connects to P0, Gnd and Power(you can still use P0 if you don't need the LEDs)
Uses a single IC buffer (SN74LV1T34DBVR) that runs on either 3.3v or 5v with a 2v in as a high state, and the rest is already 3.3v and 5v compatible so it does not matter what your upper power rail is.
It also have 4 holes as to not completely block access to the power rails underneath, so you can push 2 pairs of jumper wires down.
Available in 1-2weeks. will give schematic in case you want to use it in final product.
And I'm updating it too, no wires just plug it in it and it connects to P0, Gnd and Power(you can still use P0 if you don't need the LEDs)
Uses a single IC buffer (SN74LV1T34DBVR) that runs on either 3.3v or 5v with a 2v in as a high state, and the rest is already 3.3v and 5v compatible so it does not matter what your upper power rail is.
It also have 4 holes as to not completely block access to the power rails underneath, so you can push 2 pairs of jumper wires down.
Available in 1-2weeks. will give schematic in case you want to use it in final product.
Tony,
I just went through the image you posted, and it's brilliant! Plug-and-Play
Comments
I believe the stock went down to zero, and they did another run. I don't speak for them, but it looks like a good seller, as they have sold plenty in the last two weeks.
http://www.parallax.com/product/32111
Good luck powering such a big board off of USB - USB can only supply 0.5A, but the PPDB can use up to 1A (but I have no idea how much it uses normally without much stuff on it).
A switching regulator would certainly be nice.
This driver board really makes the LED display shine. A must have in my opinion...
http://forums.parallax.com/showthread.php/134106-Updated-17seg-LED-driver-for-PPDB-now-available.?highlight=ppdb+segment+driver
The RS-232/Max section of the board is the least utilized for me. I would not be too sad to see that go. Not sure how much longer the PS/2 jacks are going to be relevant. I use them, but would not be sad to see them replaced with something else in the next revision.
1. My copy of the PPDB has two 20-pin strips for the prop DIP instead of a socket. Because one or both strips be very slightly rotated, the spacing was not exactly 600 mils. After curling pins on two different prop DIPs, I finally was able to plug in an Augat socket which has much stiffer pins and plugged the prop chip into that. Using a proper socket would be better.
2. SIX digits of SEVENTEEN-segment LEDs for a 32-bit machine???
3. The DS1302 is really pretty obsolete.
4. I have no use at all for RS-232 or the PS-2 stuff. Or VGA.
5. Would like to have an XBee socket. Also Micro-SD.
I had the same problem getting the prop plugged in on my first PPDB. After several tries at "unmangling" the pins I finally got it more or less plugged into the sockets. There are a couple of pins that are all bented up and not actually in the socket but are making contact with the metal part with enough force to make a connection (reliable?). I'm not sure why Parallax went that route instead of an actual socket. The prop plugged into my "spare" PPDB fine.
'
If you look at were the market was back in the day, You would understand.
'
I'm not sure what Parallax was thinking with the socket either. Most new kids can't change a flat tire let alone insert a 40 pin chip into a socket.
Serial is a necessity. It's still the go-to standard for low powered device comms. Adapters are more of a problem on the PC end because Windows 7 and 8 killed a lot of the cheap ones but there are still a LOT of legacy RS232 devices, especially in industry.
PS/2 is going to be your standard for full-size keyboards. The Prop can't practically do USB, and most USB keyboards will speak PS/2 with a passive adapter. Most industrial hardened keyboards are available in PS/2, and cheap PS/2 keyboards are readily available through eBay. As for a mouse, I don't really see the need for a mouse on practical prop projects, since it can't support a true high resolution bitmap display.
Similarly, VGA is going to be your standard for video. The Prop can't do HDMI and for about $50 you can get a VGA to HDMI adapter. A few years ago I'd have wondered why no NTSC but that turned out to be prescient.
Pots, switches, and blinky LED's are always good. A SD socket would be good. Pre-wired delta sigma ADC would be nice but possibly hard with a DIP prop and the large layout. Ethernet is a bit fluid, and it's probably not worth the price hit to stick something on the PPDB that might not be favored later; remember when it was all ENC28J60? (Still is for me, but I can stick a < $20 adapter in the protoboard easily enough.) It's already got servo headers, right? How about a cheap H-bridge for linear and bipolar stepper motors?
Ah, but Tony has a one pin solution:
http://forums.parallax.com/showthread.php/134106-Updated-17seg-LED-driver-for-PPDB-now-available.
Uses a single IC buffer (SN74LV1T34DBVR) that runs on either 3.3v or 5v with a 2v in as a high state, and the rest is already 3.3v and 5v compatible so it does not matter what your upper power rail is.
It also have 4 holes as to not completely block access to the power rails underneath, so you can push 2 pairs of jumper wires down.
Available in 1-2weeks. will give schematic in case you want to use it in final product.
But seg led's is kind of old school and I have not seen any new commercial products using it.
It scrolls the text to badly.
The PPDB does need a complete overhaul, with 3" LCD and Bluetooth etc
Without a socket, if you fry your prop you lose a $150 board. With a socket, you only lose one $8 chip. You can ruin the pins of 18 props trying to get one into the socket and a socket will still be worth it. Also, it says "professional" on the tin - that implies that its typical intended user knows how to get a chip into a socket (although I would still recommend the board to beginners).
http://www.aliexpress.com/item/Free-Shipping-600-pcs-notebook-mini-PCI-E-PCIE-socket-height-4-0MM-card-slot-52PIN/1609977483.html
latch holder plastic sold separate
Breadboard is pretty old school too, why not 5 mini-PCIe slots and order your proto-type modules from oschpark
These are actually 16-segment displays. I've noticed they are often inaccurately referred to as 17-segment. http://en.wikipedia.org/wiki/Sixteen-segment_display
But my point is that with 16 segments (not counting the DP) these can be easily wired to shift registers, much like 7-segment displays are often wired and taking only 3 I/O pins regardless of how many digits you have. The caveat is you lose the DP. With a 7-segment display you usually have that extra bit available for the DP.
At the time the board was designed there was a common interface chip that was like the 16-segment version of the MAX7219. I haven't looked for it lately, however the big thing at the time was to let the Propeller multiplex the displays using shift registers.
The same argument (I/O pin count) can be used with dot-matrix displays, but the solution is similar. Multiplex to reduce overall I/O pin count.
Tony,
I just went through the image you posted, and it's brilliant! Plug-and-Play