Hey there,
I’ve been working for several years with RTOSes, including QNX, vxWorks, uCOS and recently FreeRTOS, on a wide variety of processor architectures.
These days I’m mostly working with LPC2xxx processors. It seems like freeRTOS mainly rules this family, however I’m interested in knowing if some of you have been using RTEMS on these processors?
the reason why I’m asking is because RTEMS is used on flight computers by NASA (http://www.flightsoftware.org/files/FSW08_RTEMS.pdf) and other highly reliable systems and it is free. I understand it’s fairly bulkier than FreeRTOS but it looks like there is work done towards getting it to a smaller footprint on the ARM processors. It also comes with a pre-built-in development platform for many hosts (including linux distros and macOS) which is quite the package…
Any input on running RTEMS on LPC2xxx processors will be welcome.
Thanks!
There is some stuff about RTEMS on the LPC2000 forum. I think it’s too big to be used on many of the LPC chips.
Leon
leon_heller:
There is some stuff about RTEMS on the LPC2000 forum. I think it’s too big to be used on many of the LPC chips.
Leon
Hi Leon,
This link http://www.rtems.org/wiki/index.php/Timeline specifies there is a port for ARM/Thumb that is about 15k in thumb mode. Seems like this would be a barebone system. They extend the (ROM I guess) occupation estimate to 40k, which I concur is quite large in thumb mode. Not sure how much RAM it requires though.
It seems like a port is available for the LPC2478, and rev 4.10 should be more generic for the LPC24xx family… These are not that easily usable by the typical hobbyist (in terms of packaging I guess, it’s quite a number of QFP pins to solder, and I’m not sure I’d attempt BGA reflowing) but it seems like it could fit in something like an LPC2368 or even an LPC2148…
These could definately accomodate the ROM footprint, and even 8k worth of RAM occupation, and 8k would seem like a lot for an RTOS that targets smaller to medium size embedded processors… So what I’m saying is that it may even be smaller than that, thus the interest…
jeanseb:
leon_heller:
There is some stuff about RTEMS on the LPC2000 forum. I think it’s too big to be used on many of the LPC chips.
Leon
Hi Leon,
This link http://www.rtems.org/wiki/index.php/Timeline specifies there is a port for ARM/Thumb that is about 15k in thumb mode. Seems like this would be a barebone system. They extend the (ROM I guess) occupation estimate to 40k, which I concur is quite large in thumb mode. Not sure how much RAM it requires though.
It seems like a port is available for the LPC2478, and rev 4.10 should be more generic for the LPC24xx family… These are not that easily usable by the typical hobbyist (in terms of packaging I guess, it’s quite a number of QFP pins to solder, and I’m not sure I’d attempt BGA reflowing) but it seems like it could fit in something like an LPC2368 or even an LPC2148…
These could definately accomodate the ROM footprint, and even 8k worth of RAM occupation, and 8k would seem like a lot for an RTOS that targets smaller to medium size embedded processors… So what I’m saying is that it may even be smaller than that, thus the interest…
Opps, getting exciting: http://www.rtems.org/wiki/index.php/Rtl22xx.
Apparently this would be a BSP for the LPC22xx family and “can be ported o LP21xx”… They used a board from Olimex to develop it, that all running from 512k of SRAM.
So it looks like a processor like an LP2368 with 512k of flash (cant remember) and 50k of RAM (cant remember either) may be able to run that.