Forums

RTOS Question

Started by santabarbara350z March 14, 2007
What is the most popular RTOS for the LPC2148?

I am looking at using a TCP/IP stack from InterNiche, and using the
Keil USB Mass Storage code. I am familiar with FreeRTOS, but nothing
is ported over to this family yet... so I am unsure which one to use.

An Engineer's Guide to the LPC2100 Series

----- Original Message -----
From: "santabarbara350z"
To:
Sent: Wednesday, March 14, 2007 7:40 AM
Subject: [lpc2000] RTOS Question
>What is the most popular RTOS for the LPC2148?

>I am looking at using a TCP/IP stack from InterNiche, and using the
>Keil USB Mass Storage code. I am familiar with FreeRTOS, but nothing
>is ported over to this family yet... so I am unsure which one to use.

I am not familiar with InterNiche products, but am currently working on a
FreeRTOS.org/LPC2368/lwIP project. I would say getting the stack working is
more of an integration issue than a porting issue. (Hopefully) The two
components already work in isolation, you just need to get them to work
together.

Does InterNiche provide an abstraction layer that has to be implemented for
each project? If so, how complex is it?

With lwIP there are two things, first integrating the MAC driver in the
manner expected by the lwIP stack (low level input, etc.), second there is
integrating the stack into the application. The best method of integrating
the stack into the application is going to be specific to the needs of your
particular application. You could for example run the stack in the
background, polling the MAC and performing the required timed operations as
a low priority (they don't have tight real time constraints). This would be
a simple but inflexible approach. Alternatively you could run the stack as
a high priority, blocking on MAC interrupts (as per the
FreeRTOS.org/lwIP/SAM7X demo). In the second case you just need a mechanism
(semaphore most likely) that wakes the stack task when an interrupt occurs.
There are of coarse lots of middle ways too.

Regards,
Richard.

+ http://www.FreeRTOS.org
A free real time kernel for 8, 16 and 32bit systems.

+ http://www.SafeRTOS.com
An IEC 61508 compliant real time kernel for safety related systems.
Sign up for the lpc2000 user group on Yahoo.
Go to the files section and download "lpc2148_freertos.zip" that was put
together by sashi_ono.
It works right out of the box... I have been running it for a week or so now
on my Olimex demo board.
- Grant

-----Original Message-----
From: l... [mailto:l...]On Behalf Of
FreeRTOS.org Info
Sent: Wednesday, March 14, 2007 3:57 AM
To: l...
Subject: Re: [lpc2000] RTOS Question
----- Original Message -----
From: "santabarbara350z"
To:
Sent: Wednesday, March 14, 2007 7:40 AM
Subject: [lpc2000] RTOS Question

>What is the most popular RTOS for the LPC2148?

>I am looking at using a TCP/IP stack from InterNiche, and using the
>Keil USB Mass Storage code. I am familiar with FreeRTOS, but nothing
>is ported over to this family yet... so I am unsure which one to use.

I am not familiar with InterNiche products, but am currently working on a
FreeRTOS.org/LPC2368/lwIP project. I would say getting the stack working
is
more of an integration issue than a porting issue. (Hopefully) The two
components already work in isolation, you just need to get them to work
together.

Does InterNiche provide an abstraction layer that has to be implemented
for
each project? If so, how complex is it?

With lwIP there are two things, first integrating the MAC driver in the
manner expected by the lwIP stack (low level input, etc.), second there is
integrating the stack into the application. The best method of integrating
the stack into the application is going to be specific to the needs of
your
particular application. You could for example run the stack in the
background, polling the MAC and performing the required timed operations
as
a low priority (they don't have tight real time constraints). This would
be
a simple but inflexible approach. Alternatively you could run the stack as
a high priority, blocking on MAC interrupts (as per the
FreeRTOS.org/lwIP/SAM7X demo). In the second case you just need a
mechanism
(semaphore most likely) that wakes the stack task when an interrupt
occurs.
There are of coarse lots of middle ways too.

Regards,
Richard.

+ http://www.FreeRTOS.org
A free real time kernel for 8, 16 and 32bit systems.

+ http://www.SafeRTOS.com
An IEC 61508 compliant real time kernel for safety related systems.