Frequently asked questions/Technical
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If your question is not in this FAQ, please feel free to ask it on the Mailing list
Can schematics of the gumstix motherboards or expansion boards be obtained?
gumstix publishes schematics showing the interface requirements of all the gumstix expansion boards but does not publish the schematics for the gumstix motherboards themselves.
For further information, go to Schematics.
Which external interfaces do you support?
The gumstix platforms and their related expansion boards have a very broad range of supported interfaces,
Both gumstix platforms (basix and connex) provide a 60-pin connector that gives access to 42 GPIO lines (3.3V logic), I2C, USB, JTAG, and of course, power & ground. Most of the GPIO lines can be used in a form of alternate function-- there are 3 UART ports, a NSSP, 2-PWM lines, AC97 (audio) controller, and LCD controller. there is also an MMC card slot and an optional bluetooth module on the gumstix basix platform.
for further details on the expansion capabilities of the gumstix products, go [here].
How can the timezone be set on a gumstix to GMT?
The time that linux maintains is actually maintained in UTC (aka GMT). Each process can set their notion of localtime by using the TZ environment variable.
A program can access the GMT time by using the gmtime function and can access the local time by using the localtime function.
It looks like uClibc also makes use of the /etc/TZ file if no environment variable is set. So you can set the default timezone by changing /etc/TZ and users can override that using the TZ environment variable.
Some helpful links: timezones and TZ Variable.
Can 802.11 cards, ethernet cameras, etc., be used with the gumstix?
Yes, a solution for attaching a camera to the Gumstix is to use an ethernet camera, such as the ones that DLink makes, instead of a USB one:
There's a fairly wide range of specs on the ethernet cameras and most are not much more expensive than USB cameras.
How does gumstix connect to a network?
There are several ways to connect to a network
- a waysmall computer with bluetooth and usbnet-to-bluetooth
- usbnet over a usb cable
- 10/100 with the gumstix connex platform and either etherstix, netCF, netMMC or netDUO, via a normal RJ45 cable
- wifistix and a connex platform
- gumstix Linux includes a complete TCP/IP stack, and a fully functional PPPd, which will allow a network connection to be established over any of the serial ports.
Can a Beowulf cluster of gumstix be created?
Yes. gumstix makes the full source code for the kernel and the compiler tool chain available, including a cross-compiler for the X86 platform.
Can more than 16MB of flash be obtained on a gumstix?
The engineering of the gumstix platform currently limits flash size to 16MB.
What are the performance characterstics for a gumstix ?
Check out the Benchmarks.
What technical support options are available?
Gumstix technical support is available online at no extra charge through several sources:
1) The Sourceforge Mailing list
2) The docswiki technical information pages
3) Subversion source code repository.
How can an application be ported on to the gumstix?
Gumstix Linux includes a complete Linux kernel, including all source code, plus a cross-compiler so applications can be developed on an X86 PC and then loaded to the gumstix to run.
check out the software development kit.
Why does gumstix do their own kernel development work, instead of outsourcing this to an embedded Linux specialist such as Montevista?
Initial development effort was done in-house to retain greater control over the porting process. gumstix is investigating how to meet the growing needs of our customers in this area.
How can a Linux programmer put an application onto a gumstix motherboard?
Follow these steps:
1) save the application to the MMC from your main system;
2) put the MMC into the gumstix;
3) boot the system;
4) mount the mmc;
5) run the program.
Can the waysmall computer connect to 10BaseT?
Yes, connect a waysmall computer to an ethernet network via serial-ethernet running SLIP or use usbnet over the usb port. There are several vendors of serial to ethernet adapters.
The waysmall computer contains one waysmall expansion board and either waysmall original or waysmall STUART. Each of these waysmall expansion boards have two serial ports and one usb client port from which these connections could be made.
Note that the waysmall computer may not connect to 10BaseT via an RJ45 jack as the basix platform inside the waysmall computer cannot attach to a netstix expansion board.
Which programming tools are used on the gumstix?
gumstix is programmed with freely available open source tools-- gcc-3.3.2 . gumstix engineering has used glibc, and there is a functioning uclibc toolchain and root filesystem also.
As all of the gumstix software is open source, there is no software cost for the linux software pre-loaded on the gumstix basix or connex platform.
At what speeds is the I2C bus capable of running? Just 100kHz, or can it do 400kHz as well?
According to Intel's specs, the pxa255 can run the I2C bus at 100kHz or 400 kHz.
Is a gumstix basix motherboard usable without an MMC card? If so, how much space is available in the flash?
Yes. the gumstix basix motherboard is usable without MMC. gumstix ships the basix and connex motherboards with just 2.5MB of space used for:
- the bootloader, kernel (1MB) and
- an initrd (1MB using uClibC based rdimage with busybox).
Can an SD card be used as a filesystem instead of a MMC?
Currently, there is no driver available in open source to allow an SD card to be used in the MMC card slot.
What level of performance does the 400MHz motherboard provide?
The nbench CPU benchmarking utility (with floating point tests disabled, since the Gumstix CPU has no FPU) yields:
TEST Iterations/sec. Old Index New Index Pentium 90 AMD K6/233 NUMERIC SORT 152.44 3.91 1.28 STRING SORT 10.753 4.80 0.74 BITFIELD 3.6149e+07 6.20 1.30 FP EMULATION 13.023 6.25 1.44 IDEA 393.08 6.01 1.79 HUFFMAN 21.716 0.60 0.19
Baseline: Pentium 90 with 256 KB cache running MSDOS
Baseline: AMD K6/233*, 512 KB L2-cache, gcc 2.7.2.3, libc-5.4.38, Linux 2.0.32
Bottom line: generally about the same speed, or slightly faster, than a 233MHz K6, or about 4-6 times the speed of a Pentium 90.
