So... let's imagine... These things can be run without linux. One core, one piece of RAM... Some PWM's, video generator = one cog
Let's get 8 of them, then one RPi2 to make a hub...
You certainly can connect Slave Microcontrollers to any mix of Pi i2c/SPI/UART connections.
Checking into speed-ceilings, I find one post that claims 1.2Mb/s on i2c
UARTs used to be limited by OS, but I see this post from June 2015
[The UART clock is divided from the core clock frequency and uses 16x oversampling, so the "max" baud rate is 250MHz/16 = 15.6Mbaud/s.
At such a high frequency, you will get throughput issues as the FIFOs in the UART are not very deep - 16 / 8 entries. As each entry is only 8 bytes of data, you have to service a lot of interrupts to push that much data through. 6Mbps is reasonable, but expect a core to be quite busy when running at this level of data rate.]
Other info clarifies that UART FIFO as
* separate 16×8 transmit and 16×12 receive FIFO
* control signals : s/w controlled RTC, s/w readable CTS
SPI is mentioned as 32Mbps (master)
SPI Baud is a 16b parameter (even numbers)
SPI FIFO size is 128 bytes ?
That gives quite a few options for good connection speeds to Slave Microcontrollers.
It's interesting, but what I want is a small computer with built-in WiFi, a UART, and GPIO pins. I could care less about a local keyboard, video, or sound. I'd load up some serial slave software on my robots, and use the computer as local brains that are on my WiFi network.
Attach a webcam to it, and run a web server for some remote control software and instant telepresence robot.
Everyone around here should be soldering. The smell of flux, the searing pain of scorched fingers, the wife complaining about the burn marks in the table, how else do you know you are alive?
+1. If you ain't soldering & handling lead, you ain't livin'!
Edit: MagPi magazines are being scalped on Ebay as we speak type. With that mentality, anyone finding them in-store will just buy them all. Money in the bank.
It's interesting, but what I want is a small computer with built-in WiFi, a UART, and GPIO pins.
The more glaring omission here, was a footprint option for WiFi (even a module) - plenty of room on the PCB, and they could have done two price points - $5 and <$10 ?
There are two USB connectors. One for power only. The other can connect to a tiny 2 dollar USB/WIFI dongle but you need a frikken adapter because they put a micro-USB connector on it.
I'm pretty sure you can ignore the USB power connection an power it from pins on the GPIO header.
IIRC there was another microUSB footprint on the underside. Might be another USB connection by soldering on a connector?
Not quite - looks to be 8 pins, and no thru holes on the housing PCB lands. (ie not USB, something else )
Maybe it is this, from the features list ? - An unpopulated composite video header
IIRC there was another microUSB footprint on the underside. Might be another USB connection by soldering on a connector?
Not quite - looks to be 8 pins, and no thru holes on the housing PCB lands. (ie not USB, something else )
Maybe it is this, from the features list ? - An unpopulated composite video header
Possibly with Audio included ?
The composite video header are the 2 pins at the RH end just under the 40pin connector.
There are two USB connectors. One for power only. The other can connect to a tiny 2 dollar USB/WIFI dongle but you need a frikken adapter because they put a micro-USB connector on it.
Heater, you've spoken of the $2 WiFi dongles several times now; can you provide a link ? I tried several cheaper ones that didn't work with the pre-compiled Raspbian kernel / modules (and a few hours of driver research didn't provide the joy, either), and I ended up going with the $10 one from Adafruit, which works great.
As it stands, $5 for the PiZero, $10 (or even $2) for WiFi, and $6 for an SD card doesn't compare favorably with the $9 C.H.I.P., which has WiFi, eMMC, and Bluetooth. The 1080p HDMI is cool, but I just don't need it on an embedded device.
I *am* using it with the Pi2 that I'm typing this on; I haven't used my big notebook for a couple of months now, and I don't really miss it.
Admittedly I have not tried any of them but a lot of them look like the cheap no-name WIFI dongles I have been buying locally. It is a bit of a lottery. Some dongle or other refused to work with my original two Pi. Worked fine with my friends Pi. Works fine with the new Pi 2 now. Never did figure out why.
The C.H.I.P. looks like an amazing deal. Let's see how that flies. I won't be ordering, I'm drowning in boards to try out already!
One does not want an HDMI screen on many embedded devices, but plenty of things can be souped up with a display. The Pi are not actually designed to be embedded devices, they have a different agenda.
I gave up on soldering... too old - poor eyesight and hand tremors. So I switched to FPGA devices and seeking out modular solutions. Still, I have a pile of soldering project waiting my attention. When the world went to SMDs, I began to capitulate, parts became harder to procure and everything seemed to require designing ones own board.
Loopy,
My eyesight has deteriorated and my hands shake a little. So I wear a jewellers loupe over my glasses so I can see small things. I use a makeshift bar to steady my wrist. I still manage to hand solder 0603 parts and 0.5mm pitch ICs. I now have a reflow oven so I only have to place the parts now. But I graduated to some 0402 parts and they look really small
From my posts, I think it is obvious that what I really need to be doing is to be reading more of the tutorials and code. The Propeller OBEX is a wealth of useful applications and examples and there is quite a bit of support for Spin and PASM.
Similarly, Linux has tons of documentation that I need to refine my understanding of.
Shopping for a hot new item or soldering lots of project ideas is just not where I need to focus. Also, I don't think I need to learn yet another new IDE for the Propeller.
Eben left school and got a job. That's what many people do. What are you insinuating by "went to his reward" as if there is something shady about it? Eben got an education, found something he can do very well, computing, and got a job doing it. That's what people do.
The Pi project was going on before he got to Broadcom, early prototypes used AVR. When he got there he realized they had the solution to build the machine of his dream. And so it was. I don't see any issues with that.
...his wife, Liz Upton, remains on the Raspberry Pi Foundation payroll as the communications officer.
So? I'm sure she does not take much for the work she does. You could probably find out if you check the public records on the Foundation. See below.
So I still get distinctly blurred images of the Raspberry Pi idealism.
Why on earth is that? What are you implying? Everything about the Raspberry Pi Foundation is out in the open. More so than most businesses as it's registered as a charity and as such gets a lot of regulatory scrutiny.
This is not the first time you have made these insinuations of something shady about the Foundation. I thought we sorted this out a year ago or so.
This morning I had a chance to look through the PiZero magazine issue, and one of brief articles was about a Zero badge, light goes on...
What if you took the PiZero and added a very small WiFi, and then attached this to the back of your Hackable Badge, make the connections to the 3v3 and P0,P1 for UART, what could you do then? Anything useful or interesting?
..there is a thriving group of hard core "down to the metal" Pi programmers.
Only that communication between the 8 Pi Zero and the RPi2 "HUB" is going over ethernet or serial. Dead slow.
...... But I know it's not going to be easy for anyone to use.
We have that mulit-prop thing, simillar to Beaus' high speed serial. It creates the serial channel that runs at clock speed. We can add multiple props, and they transefer at clock speed (80Mhz).
We do the same to transfer between Prop & RPi, of course it runs at prop clock speed not RPi clock.
BUT one could do the exact same with multiple RPi, to run at RPi clock speed. Recall that this is the method similar to (but different from) CSP channels, in that it sis only the low level plumbing for the data transfer, and does not include the upper level OS stuff that would be "real" CSP channels.
But the solution is there, and its very fast, and very simple, but merely lacks an application.
You're welcome. I just purchased one from Adafruit because I've been curious about the Raspberry Pi for a while. I don't plan to use video, just connect via SSH to see what sort of robots you can build with one.
I originally wanted to buy two of the little buggers from Micro Center on the Wednesday. Turns out that all three stores
are out here. (Or so the website insists. I suspect that they do not want to show inventory.) Worse luck. They do not know when they will have them in stock.
So... how many here have actually acquired a $5 Raspberry Zero? Or is that a Pi Zero, or a Raspberry Pi Zero, or merely a Zero?
And how many have acquired one at a higher cost?
It seems that the $5 USB price is only for your first one, and only for walk-in American customers (the British still use Pounds, right?). Any additional Pi Zeros, will cost $9.99USD.
Clever marketing seems to be playing into America's Black Friday launch of the Christmas shopping season.
I have never seen the price of electronic components, or anything for that matter, go up when you buy a larger quantity.
That is clever marketing indeed. Perhaps not in the way you think.
Demand is high, supply is low, at this moment. You might expect microcenter and others to exploit that situation and jack the price up. That's how things go in markets. They have not done that. Which is good of them.
They could just be nice and sell as you as many as you want for $5. As is the desired situation. They have not done that. Why not? Supply is low, demand is high, people have been profiteering by getting hold of Pi Zero cheap and offering on ebay for crazy high amounts. That means these buyers would be reaping a profit that microcenter could have had whilst at the same time ensuring that local kids who want one cheap don't get one because they are all sold out to profiteers. Microcenter have not taken this option either. Which is good of them.
So, we get the strange result that one is cheap two is expensive. This is essentially saying: We only want you to buy one so that more people get a fair chance to have one. Whist at the same time discouraging profiteering.
Brilliant. And fair and good of them.
When things have stabilized, production capacity is there and the crazy rush has subsided they will all be at the low price I'm sure.
For myself, I'm not in a hurry to get one. Without WIFI or Ethernet there is not a lot I want to do with it just now. I don't want to have to start buying a bunch of adapter cables. If it turns out we can use that USB OTG port to make the thing into a USB gadget then things migt get interesting.
Comments
Let's get 8 of them, then one RPi2 to make a hub...
Certainly you don't need Linux, there is a thriving group of hard core "down to the metal" Pi programmers.
Only that communication between the 8 Pi Zero and the RPi2 "HUB" is going over ethernet or serial. Dead slow.
Not sure what we end up with in this scheme. But I know it's not going to be easy for anyone to use.
I'm not sure it was entirely serious
You certainly can connect Slave Microcontrollers to any mix of Pi i2c/SPI/UART connections.
Checking into speed-ceilings, I find one post that claims 1.2Mb/s on i2c
UARTs used to be limited by OS, but I see this post from June 2015
[The UART clock is divided from the core clock frequency and uses 16x oversampling, so the "max" baud rate is 250MHz/16 = 15.6Mbaud/s.
At such a high frequency, you will get throughput issues as the FIFOs in the UART are not very deep - 16 / 8 entries. As each entry is only 8 bytes of data, you have to service a lot of interrupts to push that much data through. 6Mbps is reasonable, but expect a core to be quite busy when running at this level of data rate.]
Other info clarifies that UART FIFO as
* separate 16×8 transmit and 16×12 receive FIFO
* control signals : s/w controlled RTC, s/w readable CTS
SPI is mentioned as 32Mbps (master)
SPI Baud is a 16b parameter (even numbers)
SPI FIFO size is 128 bytes ?
That gives quite a few options for good connection speeds to Slave Microcontrollers.
Attach a webcam to it, and run a web server for some remote control software and instant telepresence robot.
+1. If you ain't soldering & handling lead, you ain't livin'!
Edit: MagPi magazines are being scalped on Ebay as we speak type. With that mentality, anyone finding them in-store will just buy them all. Money in the bank.
http://www.ebay.com/itm/The-MagPi-Magazine-With-Raspberry-Pi-ZERO-Issue-40-DEC-Christmas-2015-/252187102645?hash=item3ab785cdb5:g:YJ8AAOSw7FRWV0x8
The more glaring omission here, was a footprint option for WiFi (even a module) - plenty of room on the PCB, and they could have done two price points - $5 and <$10 ?
I'm pretty sure you can ignore the USB power connection an power it from pins on the GPIO header.
I have had the same dilemma for keyboard connector on my small boards - use a mini/microUSB and a cable to full USB + USB/USB adapter ???
Not quite - looks to be 8 pins, and no thru holes on the housing PCB lands. (ie not USB, something else )
Maybe it is this, from the features list ?
- An unpopulated composite video header
Possibly with Audio included ?
Hmmm, then what connects to these 8 pins, using what connector ?
Some posts suggest it is JTAG ?
Heater, you've spoken of the $2 WiFi dongles several times now; can you provide a link ? I tried several cheaper ones that didn't work with the pre-compiled Raspbian kernel / modules (and a few hours of driver research didn't provide the joy, either), and I ended up going with the $10 one from Adafruit, which works great.
As it stands, $5 for the PiZero, $10 (or even $2) for WiFi, and $6 for an SD card doesn't compare favorably with the $9 C.H.I.P., which has WiFi, eMMC, and Bluetooth. The 1080p HDMI is cool, but I just don't need it on an embedded device.
I *am* using it with the Pi2 that I'm typing this on; I haven't used my big notebook for a couple of months now, and I don't really miss it.
I was thinking of all those 2 dollar WIFI dongles available from ebay:
http://www.ebay.com/sch/i.html?_from=R40&_trksid=p2050601.m570.l1313.TR0.TRC0.H0.Xusb++wifi.TRS0&_nkw=usb++wifi&_sacat=0
Admittedly I have not tried any of them but a lot of them look like the cheap no-name WIFI dongles I have been buying locally. It is a bit of a lottery. Some dongle or other refused to work with my original two Pi. Worked fine with my friends Pi. Works fine with the new Pi 2 now. Never did figure out why.
The C.H.I.P. looks like an amazing deal. Let's see how that flies. I won't be ordering, I'm drowning in boards to try out already!
One does not want an HDMI screen on many embedded devices, but plenty of things can be souped up with a display. The Pi are not actually designed to be embedded devices, they have a different agenda.
But this should please Heater...
http://www.bloomberg.com/news/articles/2015-11-26/don-t-want-to-spend-those-extra-5-on-a-latte-buy-a-computer
I should add that while Eben Upton is indeed no longer with the Raspberry Pi Foundation, quit Cambridge acadamia, and went to his reward as an employee of Broadcom -- his wife, Liz Upton, remains on the Raspberry Pi Foundation payroll as the communications officer.
http://www.zoominfo.com/p/Liz-Upton/1758613307
https://www.raspberrypi.org/blog/author/liz/
So I still get distinctly blurred images of the Raspberry Pi idealism.
My eyesight has deteriorated and my hands shake a little. So I wear a jewellers loupe over my glasses so I can see small things. I use a makeshift bar to steady my wrist. I still manage to hand solder 0603 parts and 0.5mm pitch ICs. I now have a reflow oven so I only have to place the parts now. But I graduated to some 0402 parts and they look really small
Similarly, Linux has tons of documentation that I need to refine my understanding of.
Shopping for a hot new item or soldering lots of project ideas is just not where I need to focus. Also, I don't think I need to learn yet another new IDE for the Propeller.
https://www.raspberrypi.org/forums/viewtopic.php?f=63&t=98765, unless you have some secret news we have not heard.
Eben left school and got a job. That's what many people do. What are you insinuating by "went to his reward" as if there is something shady about it? Eben got an education, found something he can do very well, computing, and got a job doing it. That's what people do.
The Pi project was going on before he got to Broadcom, early prototypes used AVR. When he got there he realized they had the solution to build the machine of his dream. And so it was. I don't see any issues with that. So? I'm sure she does not take much for the work she does. You could probably find out if you check the public records on the Foundation. See below. Why on earth is that? What are you implying? Everything about the Raspberry Pi Foundation is out in the open. More so than most businesses as it's registered as a charity and as such gets a lot of regulatory scrutiny.
This is not the first time you have made these insinuations of something shady about the Foundation. I thought we sorted this out a year ago or so.
What if you took the PiZero and added a very small WiFi, and then attached this to the back of your Hackable Badge, make the connections to the 3v3 and P0,P1 for UART, what could you do then? Anything useful or interesting?
Ray
It's not really a good deal when everything else is factored in.
You'd be better off with a netbook.
We have that mulit-prop thing, simillar to Beaus' high speed serial. It creates the serial channel that runs at clock speed. We can add multiple props, and they transefer at clock speed (80Mhz).
We do the same to transfer between Prop & RPi, of course it runs at prop clock speed not RPi clock.
BUT one could do the exact same with multiple RPi, to run at RPi clock speed. Recall that this is the method similar to (but different from) CSP channels, in that it sis only the low level plumbing for the data transfer, and does not include the upper level OS stuff that would be "real" CSP channels.
But the solution is there, and its very fast, and very simple, but merely lacks an application.
Thanks for the tip, my local Microcenter is showing 10+ in stock.
are out here. (Or so the website insists. I suspect that they do not want to show inventory.) Worse luck. They do not know when they will have them in stock.
And how many have acquired one at a higher cost?
It seems that the $5 USB price is only for your first one, and only for walk-in American customers (the British still use Pounds, right?). Any additional Pi Zeros, will cost $9.99USD.
Clever marketing seems to be playing into America's Black Friday launch of the Christmas shopping season.
http://www.microcenter.com/product/457746/Raspberry_Pi_Zero
I guess I will have to ask a friend in Dallas to buy one, or go without.
That is clever marketing indeed. Perhaps not in the way you think.
Demand is high, supply is low, at this moment. You might expect microcenter and others to exploit that situation and jack the price up. That's how things go in markets. They have not done that. Which is good of them.
They could just be nice and sell as you as many as you want for $5. As is the desired situation. They have not done that. Why not? Supply is low, demand is high, people have been profiteering by getting hold of Pi Zero cheap and offering on ebay for crazy high amounts. That means these buyers would be reaping a profit that microcenter could have had whilst at the same time ensuring that local kids who want one cheap don't get one because they are all sold out to profiteers. Microcenter have not taken this option either. Which is good of them.
So, we get the strange result that one is cheap two is expensive. This is essentially saying: We only want you to buy one so that more people get a fair chance to have one. Whist at the same time discouraging profiteering.
Brilliant. And fair and good of them.
When things have stabilized, production capacity is there and the crazy rush has subsided they will all be at the low price I'm sure.
For myself, I'm not in a hurry to get one. Without WIFI or Ethernet there is not a lot I want to do with it just now. I don't want to have to start buying a bunch of adapter cables. If it turns out we can use that USB OTG port to make the thing into a USB gadget then things migt get interesting.