Kernel

PLCnewb

Member
Join Date
Jul 2002
Posts
1
I have a personal project building a program from scratch. Can anyone tell me what the KERNEL specifically contains? :confused:
 
It contains a good source of folate and vitamin B

It is also rich in several other nutrients too such as potassium, vitamin B6, riboflavin, vitamin C and fiber

You were referring to a kernel of corn, right?... :rolleyes:

-Eric
 
The kernel is the core of the runtime firmware

The kernel is firmware within the PLC that takes care of switching tasks between scanning the ladder, scanning the I/O, and doing the communications. In most cases there are more tasks than these as each I/O port or channel can have its own task and there may be serveral ladder task. The kernel also takes care of mutual exclusion and interrupts like those from the real time clock. This is a topic that the PLC designers may be intereseted in, but is not the users.
Check out real time operating systems.
 
Interesting in fact, but Eric's answer is the best one : each kernel contains specific components offering (or not) benefits. All depends on your final use.

Get informations and rather try to compare different OS kernels (all OS are based on a microcoded core, even the ones driving your recent VCR or camera !). But perhaps, the last Sharp camcorder's kernel would be unusable for some PLC design project (to be verified).

Some OS ideas ? : OS-9, VRTX, VxWorks, QNX, Unix, Linux, Bill's Win XYZ or Embedded Win ZYX...
Be curious but careful : you could get lost in philosophical observations (what means "PLC" ? what means "real-time" ? to be or not to be ? and many other abyssal questions)

In a hurry ? Pick out brand names on this site, and call their local offices !

Regards
 
A step above sarge :)

The kernal is a collection of routines in the computer that does certain basic tasks, like getting a key-press from the keyboard. These routines are very useful, in the same way digesting your food is useful. But like digestion, the kernal is not something you generally need to think about (unless you're lactose intolerant or something).

Basically, the kernal will mind it's own business and chug along like a good little trooper with no help from you at all. Certain advanced users can tinker with kernal routines and rev up all sorts of stuff on their control systems, but this is what separates the "Terry Woods"-people from us mere mortals (Hi Terry!)

For the test on Friday : Kernal - a collection of operating system subroutines, executed continuously to support the hardware.
 
What is a KERNEL?
It is the central module of an operating system. It is the part of the operating system that loads first, and it remains in main memory. Because it stays in memory, it is important for the kernel to be as small as possible while still providing all the essential services required by other parts of the operating system and applications. Typically, the kernel is responsible for memory management, process and task management, and disk management.

Kind of combine some of the answers used here to apply to plc's. Peter stated it is Firmware (software written onto ROM, prom or eprom) and this makes sense because the operating system for a plc must already exist because there has to be something there to know when we connect and download a program.

This is another one of those ambitious type projects because it involves working at the core of the microprocessor, rom, ram etc. You may want to look at the robotic sites for more info on microprocessors, stamps etc.

LOOK closely at this site http://www.robotics.com/robots.html

IF you want to see a kernel you can checkout the Linux sites and get the open code for their kernel(s).

Actually Peter's last remark stating look at real time operating systems was another good one. RTOS are the foundation for using microcontroller(s). You can be sure if Peter said it then look at what he says because it will lead you in the right direction.
 

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