If you wanted a solution that works on osx but hardly anywhere else then you can write a cdc device and use vendor control messages to set the pins. unlike linux, osx lets you send control messages without unloading the drivers. I used it to write a mac specific usb serial adapter with built in servo drivers where the servo control was all handled through the control messages.
mchck: $7 Cortex-M0 board
(48 posts) (12 voices)-
gbulmer
Moderatorfeurig - "If you wanted a solution that works on osx but hardly anywhere else then you can write a cdc device and use vendor control messages to set the pins."
"Mac only" is a minority of users round here, though more than just me. So that wouldn't be a good path :-(
Thanks again for your help and advice.
Posted 3 years ago # -
gbulmer
Moderatorfeurig - "Actually ... apple implemented the IAD (after years of hounding) on Snow Leopard and beyond. (intel only). So technically it is supported as long as you are willing to go 64 bit intel.
Okay, so 64-bit Intel, but does that have a bad interaction with Java (i.e. the Arduino and Maple IDE)? IIRC I had to set the IDE to 32-bit to get the code to run; and I think the serial library was in-process.
The mcp2200 is as good as the cp2102 and the underlying cpu is a pic18f14k50 So you get the best of both worlds.
Does that mean the MCP2200 can have user-programs loaded too?We look forward to further news on your developments :-)
Posted 3 years ago # -
gbulmer
Moderatortormod - Thanks, very interesting suggestion.
As you say, PL2303 $0.32 for 100 off, eg: http://www.aliexpress.com/item/USB-IC-PL2303HX-PL2303/657757063.htmlI think they may be low-cost because:
A. Prolific have end-of-life'd: "PL-2303HX (Chip Rev A) will be phased out at the end of October 2012" http://prolificusa.com/portfolio/pl-2303hx-usb-to-serial-bridge-controller
B. It needs an external crystal.Have you any experience with the PL2303? Does it work okay on Mac & Linux?
Posted 3 years ago # -
mikep
MemberAFAIK, the PL2303 is used in those data cables for Nokia phones (DKU-5 and CA-42, http://dx.com/p/dku-5-data-cable-fully-compatible-with-nokia-dku-5-cell-phone-data-cable-13863?r=58979887, http://dx.com/p/data-cable-compatible-with-nokia-ca-42-446?rt=1&p=2&m=2&r=3&k=1&t=1&s=13863&u=446).
I have used one of these cables as a cheap serial-USB converter. It's 3.3V level and you only get RX and TX and GND (no additional signals, at least not on the cable I had). I only used it on windows though. But from what I read it should be recognized on Linux as well. They're pretty popular for debricking a router or a Seagate Dockstar ...http://buffalo.nas-central.org/index.php/Use_a_Nokia_Serial_Cable_on_an_ARM9_Linkstation
Posted 3 years ago # -
tormod
MemberI have used pl2303 a lot on Linux with good experience in our labs interfacing various RS232-equipped gear. It is used in the very common dongles that look like this: http://uk.farnell.com/tripp-lite/u209-000-r/adapter-usb-a-to-male-serial-17/dp/1838797 with semi-transparent housing and a LED (I think the original design is "UC-232A" from Aten International Co.).
They work on Mac OS X also, if you use the right driver, see https://code.google.com/p/stm32flash/issues/detail?id=36
Good point about the external crystal. That is a good way to guess what the chip is if you can spot a crystal in the adapter. And don't forget the USB connector in the budget, if you compare cost with separate USB/UART adapters.
For separate, 3.3V USB/UART boards I prefer the CP2102-based ones from Baite because they have more pinouts (although not all headers soldered).
I only have one bad experience with a cheap PL2303 based adapter where the RX input impedance was too low and it pulled down the signal from the MAX232 in the other end, but I don't know if the chip itself was to blame.
Posted 3 years ago # -
gbulmer
Moderatormconners - all of those ST Discovery boards are great value. The VL part has lots of peripherals on-board.
AFAIK, the only down-side of the STM32VL is the programmer is an ST-LINK and not an ST-LINK/V2. The V2 plays better with Mac.
ST's standard peripheral library is a bit ugly, but it is much, much better than nothing.
The amazing value-for-money of the Discovery boards is they all have an on-board hardware debugger! Single-step, breakpoints, trigger a breakpoint when data is changed, interrupt a running program. Brilliant!
If you want to use gdb, have a look at https://github.com/texane/stlink
STM32F3Discovery is even better! As you can guess, I am a fan :-)
Posted 2 years ago # -
mconners
Membergbulmer, the main reasons I bought them, one you had commended them to me a while back, two http://www.cs.indiana.edu/~geobrown/book.pdf I got that link off of the arm.com web site. As part of their university program, that is the lab manual for the Featured Arm Course. The prof seems like an old school guy, he features the STM32LVL on linux and Mac all command line and interfaces with several periperals. Everything I've learned about ARM I've taught myself so having someone else's perspective is great, plus once you learn everything on the command line the gui's are a snap.
Thanks again,
Mike
Posted 2 years ago # -
gbulmer
Moderatormconners - Thank you for posting the book link to the forum. A friend had sent me a link recently, bit I had forgotten about it.
I have skimmed it, and came to the same conclusion as you, that it was very solid "old school" stuff, and valuable to everyone who wants to get under the skin of the IDE GUI, or have portable skills.
Oddly enough, I did a public presentation last night about "Under the covers of Arduino", covering tool chain, in-memory layout (process) and how that works, as well the GPIO peripheral. So I can confirm there are folks who'd like to understand what actually is going on.
Posted 2 years ago #
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