Forums

Favorite Philips/NXP LPC21xx websites/forums?

Started by John September 14, 2006
Hi,

I've recently started development with a Philips LPC2103.  I know Atmel 
has a site, AT91.com, which I found useful for AT91SAM stuff.  I'm 
looking for suggestions or recommendations on websites/forums that 
discuss using the LPC21xx parts.  

I did the Google search already but ended up at sites that archive "the 
real" forums.

If it makes a difference, I'm planning on using the GNU toolchain 
w/Eclipse and a Chameleon POD/OpenOCD for JTAG.  I already have an 
Olimex board with the 2103.

Thanks!

John schrieb:

> I've recently started development with a Philips LPC2103. I know Atmel > has a site, AT91.com, which I found useful for AT91SAM stuff. I'm > looking for suggestions or recommendations on websites/forums that > discuss using the LPC21xx parts.
Personally, I really dislike web forums - but there is a reasonably active group on Yahoo: <http://tech.groups.yahoo.com/group/lpc2000/> Tilmann -- http://www.autometer.de - Elektronik nach Ma&#2013265951;.
On Thu, 14 Sep 2006 08:39:55 GMT, John wrote:
/cut

I have Keil MCB2100 with LPC2129 ARM7TDMI microcontroller board.
There are not many sites with information about LPC.

yahoo lpc2000 group mostly.

Best bet is to ask here if you need something or don't undestand.
John wrote:
> If it makes a difference, I'm planning on using the GNU toolchain > w/Eclipse and a Chameleon POD/OpenOCD for JTAG. I already have an > Olimex board with the 2103.
The author of OpenOCD is active in a forum with that name at the Sparkfun web site (US distributer of Olimex products). Sparkfun is a good company and they have other families of devices also. The lpc2103 is very attractive (32 bit performance with a cost and power consumption profile of an 8 or 16 bit processor). I really wish they didn't get bought by an investment group with a mixed history, though (I assume you know Philips Semiconductor is now NXP). Philips always seemed to offer poor support to small companies and I can't imagine that this will improve with their new owners. They always seemed to have too few people handling customer service and those limited resources were apparently targetted at their bigger customers. However, the Yahoo lpc2000 group is very good. I wish some of the posters there wouldn't check their manners at the door, though. Atmel is quite different but they don't have any low-end Arm7 parts in this category. I've been looking at Luminary lately... Eric
Hi,

Thanks to all who responded, this is exactly the information I was 
seeking!

In article <1158362086.029045.144770@e3g2000cwe.googlegroups.com>, 
englere wrote:
> The lpc2103 is very attractive (32 bit performance with a cost and > power consumption profile of an 8 or 16 bit processor). I really wish > they didn't get bought by an investment group with a mixed history, > though (I assume you know Philips Semiconductor is now NXP).
Yes, I heard about this NXP nonsense. I went to the Philips website one day and I was trying to find the LPC datasheet. I accidentally hit play on a flash item (I use "Flashblock" for Firefox so I'm not normally assaulted by this crap) and there was some marketish looking dude spouting nonsense quite loudly.
> Philips always seemed to offer poor support to small companies and I > can't imagine that this will improve with their new owners. They always > seemed to have too few people handling customer service and those > limited resources were apparently targetted at their bigger customers.
This has been my past experience as well. In fact, this is the first Philips part I have considered using in 8+ years. They're on my blacklist and except for this, they'll remain there.
> Atmel is quite different but they don't have any low-end Arm7 parts in > this category. I've been looking at Luminary lately...
It seems their AT91SAM32 is the "low-end". Fortunately with Philips in the game, the price on the AT91SAM parts has come down. They're now $5ish in 100 pcs quantities, DigiKey pricing, where they used to be $6.74 in 1k+. The only thing I don't like so far about the LPC parts (from looking at the data sheets), it seems they have just plonked down the ARM "VIC" Interrupt Controller instead of making their own. Atmel's interrupt controllers seem much more intelligently designed. I like the idea of writing interrupt handlers per event (UART_RX, UART_TX). With the LPC parts it seems the peripheral interrupt handler must determine the cause (RX, TX, etc) and then take appropriate action. Anyway, I'd be interested to hear other minuses/pluses of the LPC parts. Thanks, John.
John wrote:

> It seems their AT91SAM32 is the "low-end". Fortunately with Philips in > the game, the price on the AT91SAM parts has come down. They're now > $5ish in 100 pcs quantities
Sounds good - it's worth a look. I bet they use more current than the 2103, but that's not an issue if you aren't using battery power.
> Anyway, I'd be interested to hear other minuses/pluses of the LPC parts.
Despite my negative comments about the company, the 2103 has a lot going for it. It has high speed bit toggling (I think it's 3 or 4 times faster than most Arm7's), and I think all lpc2000 devices have the MAM that lets them run full speed from flash. The SAM devices run about half speed from flash. Although the lpc on-chip peripherals are simpler than those of the SAM, that simplicity can be a good thing if you're in a hurry to get something working. I haven't compared the errata sheets, but I'd expect the SAM to have more items there because their chips are generally more complex. But I don't mean this as a slam against Atmel because every company has these kinds of issues when they pack more stuff into the chip. If you have a need for a battery powered Arm device, the lpc2103 is your best bet today. If power isn't a concern and you just need a low cost device, then compare the SAM32 against the 2103 and see how the specs line up. Eric
"Eric" <englere_geo@yahoo.com> skrev i meddelandet 
news:1158461367.018532.249200@h48g2000cwc.googlegroups.com...
> John wrote: > >> It seems their AT91SAM32 is the "low-end". Fortunately with Philips in >> the game, the price on the AT91SAM parts has come down. They're now >> $5ish in 100 pcs quantities
For now, a SAM7S16 is in design and is pin compatible with the S321/S32.
> > Sounds good - it's worth a look. I bet they use more current than the > 2103, but that's not an issue if you aren't using battery power. > >> Anyway, I'd be interested to hear other minuses/pluses of the LPC parts. > > Despite my negative comments about the company, the 2103 has a lot > going for it. It has high speed bit toggling (I think it's 3 or 4 times > faster than most Arm7's), and I think all lpc2000 devices have the MAM > that lets them run full speed from flash. The SAM devices run about > half speed from flash.
If you run in Thumb mode, you run full speed and since the SAM7 only has a single waitstate, it should be faster than the LPC at any given frequency. If you know you run at low enough temp, you could test setting zero waitstates at 48 MHz. You could be surprised... Also, if you have some communication tasks, then you find that the PDC will off load the CPU significantly while the LPC gets bogged down. Also, for some small compute intensive tasks, it is quite OK to copy and execute from SRAM, the SAM7 has plenty of that.
> > Although the lpc on-chip peripherals are simpler than those of the SAM, > that simplicity can be a good thing if you're in a hurry to get > something working.
Then again, once you are deep in the project and try to solve the hard problems then you appreciate the SAM7 peripherals.
> I haven't compared the errata sheets, but I'd expect the SAM to have > more items there because their chips are generally more complex. But I > don't mean this as a slam against Atmel because every company has these > kinds of issues when they pack more stuff into the chip.
> If you have a need for a battery powered Arm device, the lpc2103 is > your best bet today. If power isn't a concern and you just need a low > cost device, then compare the SAM32 against the 2103 and see how the > specs line up.
It depends on the conditions. The PDC of the SAM parts allows you to do a lot while the CPU is sleeping.
> > Eric
-- Best Regards, Ulf Samuelsson This is intended to be my personal opinion which may, or may not be shared by my employer Atmel Nordic AB
Ulf Samuelsson wrote:
> "Eric" <englere_geo@yahoo.com> skrev i meddelandet > news:1158461367.018532.249200@h48g2000cwc.googlegroups.com... > >>John wrote: >> >> >>>It seems their AT91SAM32 is the "low-end". Fortunately with Philips in >>>the game, the price on the AT91SAM parts has come down. They're now >>>$5ish in 100 pcs quantities > > > For now, a SAM7S16 is in design and is pin compatible with the S321/S32. > > >>Sounds good - it's worth a look. I bet they use more current than the >>2103, but that's not an issue if you aren't using battery power. >> >> >>>Anyway, I'd be interested to hear other minuses/pluses of the LPC parts. >> >>Despite my negative comments about the company, the 2103 has a lot >>going for it. It has high speed bit toggling (I think it's 3 or 4 times >>faster than most Arm7's), and I think all lpc2000 devices have the MAM >>that lets them run full speed from flash. The SAM devices run about >>half speed from flash. > > > If you run in Thumb mode, you run full speed and since the SAM7 only has a > single waitstate, > it should be faster than the LPC at any given frequency. > If you know you run at low enough temp, you could test setting zero > waitstates at 48 MHz. > You could be surprised... > > Also, if you have some communication tasks, then you find that the PDC will > off load the CPU significantly while the LPC gets bogged down. > Also, for some small compute intensive tasks, it is quite OK to copy and > execute > from SRAM, the SAM7 has plenty of that.
How much SRAM is in the SAM7S16 you mention ? -jg
>> Also, if you have some communication tasks, then you find that the PDC >> will >> off load the CPU significantly while the LPC gets bogged down. >> Also, for some small compute intensive tasks, it is quite OK to copy and >> execute >> from SRAM, the SAM7 has plenty of that. > > How much SRAM is in the SAM7S16 you mention ? > > -jg
Not sure, 4-8kB so the idea of copying to SRAM is less useful for this chip. With 64 kB SRAM in the AT91SAM7S256 it is a very good proposition. -- Best Regards, Ulf Samuelsson This is intended to be my personal opinion which may, or may not be shared by my employer Atmel Nordic AB
Eric wrote:
> John wrote: > > > It seems their AT91SAM32 is the "low-end". Fortunately with Philips in > > the game, the price on the AT91SAM parts has come down. They're now > > $5ish in 100 pcs quantities > > Sounds good - it's worth a look. I bet they use more current than the > 2103, but that's not an issue if you aren't using battery power.
Actually my experience is that the Atmel parts are the lowest power you can find. Of course this will depend on any number of things and since Philips is a close second, for any given app the Philips parts may be lower power. But don't assume the Atmel parts are hogs, they are not! They are a bit more money than the Philips parts. I don't know exactly what makes them more expensive, but we buy a lot of parts and get high quantity pricing with a lot of competition. Even so, the Atmel prices were all a bit higher than the equivalent Philips parts. We went with the Atmel parts on our first few ARM designs because most of our stuff runs from battery and power is very important. The Atmel parts have some clear advantages for low power operation.
> > Anyway, I'd be interested to hear other minuses/pluses of the LPC parts. > > Despite my negative comments about the company, the 2103 has a lot > going for it. It has high speed bit toggling (I think it's 3 or 4 times > faster than most Arm7's), and I think all lpc2000 devices have the MAM > that lets them run full speed from flash. The SAM devices run about > half speed from flash.
The bit toggling on the newer Philips parts is a lot faster than the older Philips parts, but the Atmel parts have always been fast. The original Philips design put the GPIO interface on the slow internal bus. They changed that with the last few iterations of new designs.
> Although the lpc on-chip peripherals are simpler than those of the SAM, > that simplicity can be a good thing if you're in a hurry to get > something working. > > I haven't compared the errata sheets, but I'd expect the SAM to have > more items there because their chips are generally more complex. But I > don't mean this as a slam against Atmel because every company has these > kinds of issues when they pack more stuff into the chip.
You really shouldn't say stuff like this unless you look at the errata sheets. You can assume anything you want, but you know what happens then!!!
> If you have a need for a battery powered Arm device, the lpc2103 is > your best bet today. If power isn't a concern and you just need a low > cost device, then compare the SAM32 against the 2103 and see how the > specs line up.
You should look harder at the Atmel parts. Not only do they do very well on battery power running full out, they have a lot more potential for power savings by shutting down various sections of the chip and even running the internal Vddcore from an external 1.8 volt source rather than a 3.3 volt on the internal LDO. A very small switcher can give you an 80% boost in battery time just from this feature.