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Flash mcu with SPI slave capable of 16MHz operation?

Started by Antti May 7, 2007
I guess none available :(

all seem limit to clock/4 or something

but maybe I have missed some good part?

Antti

On May 7, 9:29 am, Antti <Antti.Luk...@xilant.com> wrote:
> I guess none available :( > > all seem limit to clock/4 or something > > but maybe I have missed some good part? > > Antti
Take look at Philips LPC213x. SPI1 port frequency is calculated as follows: PCLK / (CPSDVSR * [SCR+1]). PCLK=60MHz, CPSDVSRmin =2 and SCR =0. Wich gives 30MHz! Regards, M.
On 7 Mai, 09:54, Maki <prase.ruzica...@gmail.com> wrote:
> On May 7, 9:29 am, Antti <Antti.Luk...@xilant.com> wrote: > > > I guess none available :( > > > all seem limit to clock/4 or something > > > but maybe I have missed some good part? > > > Antti > > Take look at Philips LPC213x. SPI1 port frequency is calculated as > follows: PCLK / (CPSDVSR * [SCR+1]). > PCLK=60MHz, CPSDVSRmin =2 and SCR =0. Wich gives 30MHz! > > Regards, > M.
hm you mean SSP ? SPI on LPC213x ia 1/8 of clock and for the SSP, gosh I think I need to go to elementary school or something, the document called "datasheet" includes virtually info about the SSP useage, hope I find the correct datasheet also somewhere. if it really can handle 16mhz spi slave would be real nice thanks for the hint
Antti wrote:
> you mean SSP ? > SPI on LPC213x ia 1/8 of clock > > and for the SSP, gosh I think I need to go to elementary school or > something, > the document called "datasheet" includes virtually info about the SSP > useage, > hope I find the correct datasheet also somewhere. > if it really can handle 16mhz spi slave would be real nice > > thanks for the hint
Hello Antti, you have to look for the User's manual to find some meaningful documentation on the LPC2000 chips. The LPC213x UM says that when the SSP is used in slave mode, CPSDVSRmin is 12 instead of 2, leading to a much lower frequency. Regards, Dominic
On May 7, 10:46 am, Dominic <Dominic.at.use...@gmx.com> wrote:
> Antti wrote: > > you mean SSP ? > > SPI on LPC213x ia 1/8 of clock > > > and for the SSP, gosh I think I need to go to elementary school or > > something, > > the document called "datasheet" includes virtually info about the SSP > > useage, > > hope I find the correct datasheet also somewhere. > > if it really can handle 16mhz spi slave would be real nice > > > thanks for the hint > > Hello Antti, > > you have to look for the User's manual to find some meaningful documentation > on the LPC2000 chips. > > The LPC213x UM says that when the SSP is used in slave mode, CPSDVSRmin is > 12 instead of 2, leading to a much lower frequency. > > Regards, > > Dominic
Thank You Dominic for a correction. I was supeficial. Best regards, M.
Antti wrote:
> I guess none available :( > > all seem limit to clock/4 or something > > but maybe I have missed some good part? > > Antti
Hi Antti, No, I think you are pretty much right. There are ones that will run typically /2 on master mode, but to operate in slave, takes more clocks (/4 or more), and some are many more(/10). So, generaly you'd need to target the fastest clock speeds, to get 16MHz, > 64MHz, or 128MHz is suggested. The AT32UC3A0512 looks fast in master, but I did not see a fMAX in slave mode. AT91SAM9260 info suggests ~32ns in slave, but lacks any CLK ratio specs, and there must be some. AT91SAM9XE512 is the upcomming flash ARM9, which is likely to have a high CPU Clk, so give better peripheral speeds. The C8051F41x slave is /10 full duplex, and /4 half duplex, makes 5Mhz and 12.5Mhz slave speeds. AT89LPxx spec /4 in fastest SPI mode. LPC24xx specs CLK/8 as fmax. I think they all sample the SPI pins, as being simplest. Easiest to design and test. In theory, I guess one could dual port a SPI, and have a genuine high slave speed, but that's not an area the designers have targeted. You could always use a CPLD, if it must run in slave mode ? -jg
On 7 Mai, 10:46, Dominic <Dominic.at.use...@gmx.com> wrote:
> Antti wrote: > > you mean SSP ? > > SPI on LPC213x ia 1/8 of clock > > > and for the SSP, gosh I think I need to go to elementary school or > > something, > > the document called "datasheet" includes virtually info about the SSP > > useage, > > hope I find the correct datasheet also somewhere. > > if it really can handle 16mhz spi slave would be real nice > > > thanks for the hint > > Hello Antti, > > you have to look for the User's manual to find some meaningful documentation > on the LPC2000 chips. > > The LPC213x UM says that when the SSP is used in slave mode, CPSDVSRmin is > 12 instead of 2, leading to a much lower frequency. > > Regards, > > Dominic
Thanks Dominic! well this clears it for LPCxxxx :( and the user manual, I LOOKED FOR it at NXP website, its not there ! (or hidden...) but google finds from mct.net :) thanks again and I keep looking for alternatives Antti
On 7 Mai, 11:03, Jim Granville <no.s...@designtools.maps.co.nz> wrote:
> Antti wrote: > > I guess none available :( > > > all seem limit to clock/4 or something > > > but maybe I have missed some good part? > > > Antti > > Hi Antti, > No, I think you are pretty much right. > There are ones that will run typically /2 on master mode, > but to operate in slave, takes more clocks (/4 or more), and some are > many more(/10). > > So, generaly you'd need to target the fastest clock speeds, to > get 16MHz, > 64MHz, or 128MHz is suggested. > > The AT32UC3A0512 looks fast in master, but I did not > see a fMAX in slave mode. > AT91SAM9260 info suggests ~32ns in slave, but lacks any > CLK ratio specs, and there must be some. > > AT91SAM9XE512 is the upcomming flash ARM9, which is likely > to have a high CPU Clk, so give better peripheral speeds. > > The C8051F41x slave is /10 full duplex, and /4 half duplex, makes > 5Mhz and 12.5Mhz slave speeds. > > AT89LPxx spec /4 in fastest SPI mode. > > LPC24xx specs CLK/8 as fmax. > > I think they all sample the SPI pins, as being simplest. > Easiest to design and test. > In theory, I guess one could dual port a SPI, and have a genuine > high slave speed, but that's not an area the designers have targeted. > > You could always use a CPLD, if it must run in slave mode ? > > -jg
Hi Jim, you made summary of what I was afraid the situation is. BOM cost needs to be around 3USD and it must be available now. I possible have to go CPLD+MCU (BOM 2.8USD) or even FPGA+MCU (BOM 3.90USD) there is also PCB space constraints so only can use microBGA or small QFN if I can fit the needed stuff into XC9572XL then I may use that solution. the function needed is rather simple, so I was hoping to reduce the component count to flash mcu only. optionally could use 1 FPGA but that would kill BOM limits. the gadget is special serial memory emulator, that need to handle certain protocol at 16mhz. it doesnt directly map to any available spi flash memories, so need kind of serial protocol converter. Antti
Antti wrote:

> Hi Jim, > > you made summary of what I was afraid the situation is. > BOM cost needs to be around 3USD and it must be available now. > > I possible have to go CPLD+MCU (BOM 2.8USD) or even FPGA+MCU (BOM > 3.90USD) > there is also PCB space constraints so only can use microBGA or small > QFN > if I can fit the needed stuff into XC9572XL then I may use that > solution. > the function needed is rather simple, so I was hoping to reduce the > component > count to flash mcu only. optionally could use 1 FPGA but that would > kill BOM limits. > > the gadget is special serial memory emulator, > that need to handle certain protocol at 16mhz. > it doesnt directly map to any available spi flash memories, so need > kind of serial protocol converter.
How much code Size / CPU muscle appx do you need ? -jg
Subject: Flash mcu with SPI slave capable of 16MHz operation?


>I guess none available :( > > all seem limit to clock/4 or something > > but maybe I have missed some good part? > > Antti >
Why need a flash MCU? Protection? An AT91SAM9261 has 160 kB of internal SRAM which can be used for code & data. It can load the SRAM from a cheap 1 Mbit serial flash. Running the bus at 96 MHz you have 96/16 = 6 times overclocking which should be good enough! Your CPU will run at 200 MIPS+ as well from the TCM. -- 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