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2005-01-18 by RW Concepts - enquiries
I've been looking at using an LPC22XX device as I want an external memory bus. The thing is I've never seen any postings about this range which leads me to think that everyone's using a 21XX device. This can't be the case, can it? TIA. Rog. [Non-text portions of this message have been removed]
2005-01-18 by Gus
I have ben using LPC21 for a while and now thinking about using LPC22 for a new project. Same as you, I would like to know if people haveing issues with it. - What RAM chips everyone is using? - What FLASH is used? - Anything else we should be aware as far as the external bus? - From my understanding, the external bus have a fixed speed for the whole address range, is this true? I mean, if we have fast RAM and slow FLASH on the same chip we would have to run the chip to the speed of the slow device (FLASH in this example.) Thanks, Gus --- In lpc2000@yahoogroups.com, "RW Concepts - enquiries" <enquiries@r...> wrote: > I've been looking at using an LPC22XX device as I want an external memory bus. The thing is I've never seen any postings about this range which leads me to think that everyone's using a 21XX device. This can't be the case, can it?
> > TIA. > > Rog. > > [Non-text portions of this message have been removed]
2005-01-18 by Bill Knight
We have an LPC2214/2292 board at http://www.theARMPatch.com which has 12ns static RAM, a CS8900, and a CompactFlash interface on its external data bus. The speed and bus width can be different for each external chip select. Regards -Bill Knight http://www.thARMPatch.com On Tue, 18 Jan 2005 18:16:11 -0000, Gus wrote: I have ben using LPC21 for a while and now thinking about using LPC22 for a new project. Same as you, I would like to know if people haveing issues with it. - What RAM chips everyone is using? - What FLASH is used? - Anything else we should be aware as far as the external bus? - From my understanding, the external bus have a fixed speed for the whole address range, is this true? I mean, if we have fast RAM and slow FLASH on the same chip we would have to run the chip to the speed of the slow device (FLASH in this example.) Thanks, Gus --- In lpc2000@yahoogroups.com, "RW Concepts - enquiries" <enquiries@r...> wrote: > I've been looking at using an LPC22XX device as I want an external memory bus. The thing is I've never seen any postings about this range which leads me to think that everyone's using a 21XX device. This can't be the case, can it?
> > TIA. > > Rog.
2005-01-18 by Mark Crow
I (we) have been developing on a 2214 for many months now...and are using external SRAM, FLASH and a CPLD on the address/data bus. Works well...
-----Original Message-----
From: RW Concepts - enquiries [mailto:enquiries@...]
Sent: Tuesday, January 18, 2005 12:58 PM
To: lpc2000@yahoogroups.com
Subject: [lpc2000] LPC22XX usage
I've been looking at using an LPC22XX device as I want an external memory
bus. The thing is I've never seen any postings about this range which leads
me to think that everyone's using a 21XX device. This can't be the case, can
it?
TIA.
Rog.
[Non-text portions of this message have been removed]
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[Non-text portions of this message have been removed]2005-01-19 by acetoel
Hello... which SRAM and Flash Chips are you using? I'm searching for something in a easy to solder package... Thanks Ezequiel --- In lpc2000@yahoogroups.com, "Mark Crow" <mcrow@p...> wrote: > I (we) have been developing on a 2214 for many months now...and are using > external SRAM, FLASH and a CPLD on the address/data bus. Works well... > -----Original Message----- > From: RW Concepts - enquiries [mailto:enquiries@r...] > Sent: Tuesday, January 18, 2005 12:58 PM > To: lpc2000@yahoogroups.com > Subject: [lpc2000] LPC22XX usage > > > I've been looking at using an LPC22XX device as I want an external memory > bus. The thing is I've never seen any postings about this range which leads > me to think that everyone's using a 21XX device. This can't be the case, can > it? > > TIA. > > Rog. > > [Non-text portions of this message have been removed] > > > > ---------------------------------------------------------------------------- > -- > Yahoo! Groups Links > > a.. To visit your group on the web, go to: > http://groups.yahoo.com/group/lpc2000/ > > b.. To unsubscribe from this group, send an email to: > lpc2000-unsubscribe@yahoogroups.com > > c.. Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
> > > > [Non-text portions of this message have been removed]
2005-01-19 by Kerem Or
No. I am using LPC2214. What is it you would like to know ? Kerem ----- Original Message -----
From: "RW Concepts - enquiries" <enquiries@...> To: <lpc2000@yahoogroups.com> Sent: Tuesday, January 18, 2005 7:58 PM Subject: [lpc2000] LPC22XX usage > > I've been looking at using an LPC22XX device as I want an external memory > bus. The thing is I've never seen any postings about this range which > leads me to think that everyone's using a 21XX device. This can't be the > case, can it? > > TIA. > > Rog. > > [Non-text portions of this message have been removed] > > > > > Yahoo! Groups Links > > > > > > > >
2005-01-19 by Kerem Or
I'm using 16 bit wide Toshiba's SRAM (currently 1Mx16 - pcb supports upto 16MB) and Toshiba's Flash (1Mx16 - pcb supports upto 16MB). They have different access times; 70ns and 90ns respectively. Each CS# line can be programmed to support different memory timings. So the external bus does not have fixed speed. Timings change as programmed for CS0#,CS1,CS2 and CS3# lines. Of course more chip select signal can be generated but will inherit the properties of one of the 4 cs lines unless you have an external hardware to work otherwise. Few things to be aware of when interfacing external memory: - Series termination would be considered for the data and address lines - BL0# signal must be used for 8 bit devices as the uP never asserts WR# signal for 8 bit access. I'have tested SRAM (read/write patterns) and Flash (read, program, chip erase, sector erase, etc.) at 60MHz and they both worked fine. Hope this answers your questions. Kerem ----- Original Message -----
From: "Gus" <gus_is_working@...> To: <lpc2000@yahoogroups.com> Sent: Tuesday, January 18, 2005 8:16 PM Subject: [lpc2000] Re: LPC22XX usage > > > I have ben using LPC21 for a while and now thinking about using > LPC22 for a new project. Same as you, I would like to know if people > haveing issues with it. > > - What RAM chips everyone is using? > - What FLASH is used? > - Anything else we should be aware as far as the external bus? > - From my understanding, the external bus have a fixed speed for the > whole address range, is this true? I mean, if we have fast RAM and > slow FLASH on the same chip we would have to run the chip to the > speed of the slow device (FLASH in this example.) > > Thanks, > > Gus > > --- In lpc2000@yahoogroups.com, "RW Concepts - enquiries" > <enquiries@r...> wrote: >> I've been looking at using an LPC22XX device as I want an external > memory bus. The thing is I've never seen any postings about this > range which leads me to think that everyone's using a 21XX device. > This can't be the case, can it? >> >> TIA. >> >> Rog. >> >> [Non-text portions of this message have been removed] > > > > > > > Yahoo! Groups Links > > > > > > > >