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robleso7473
Joined: 25 Mar 2009 Posts: 47
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Is 18F67J60 ethernet uC still popular |
Posted: Wed Jun 29, 2011 2:12 pm |
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This is more of a higher level question on what the state of the 18F67J60 ethernet uC status. I know it's still being sold but most of reference designs and app notes date back to 2007.
Did it fall out of favor for some new uC or are there bugs associated it with it that I don't know about.
Any info would be helpful as I'm contemplating using it in a future design.
Thanks,
Oscar |
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temtronic
Joined: 01 Jul 2010 Posts: 9221 Location: Greensville,Ontario
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Posted: Wed Jun 29, 2011 4:43 pm |
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As with all microcomputers ( actually all ICs) if you wait a week or two, someone will have a 'newer,bigger,better,cheaper' chip. As to whether they are 'better' for you it depends upon if you need the new features. Just because a product comes out doesn't mean it'll perform any better than what you have now.There's a lot to be said about something that's 'tried and true'.Also depending upon production/inventory levels it might be better to keep what you have.If you don't need all the new 'bells and whistles,why invest the time and resources into R&Ding to see if the 'new' PIC is better!
Yes, it's nice to have more memory and onboard peripherals for 'future' use however careful programming can always squeeze more code into the silicon.
If the new chip is pin for pin compatible, that really helps the decision as R&D 'proof of concept' ( does it really work !) can be done in a day or two.
Providing of course the code can be ported over easily. |
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asmallri
Joined: 12 Aug 2004 Posts: 1634 Location: Perth, Australia
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Re: Is 18F67J60 ethernet uC still popular |
Posted: Wed Jun 29, 2011 8:31 pm |
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robleso7473 wrote: | This is more of a higher level question on what the state of the 18F67J60 ethernet uC status. I know it's still being sold but most of reference designs and app notes date back to 2007.
Did it fall out of favor for some new uC or are there bugs associated it with it that I don't know about.
Any info would be helpful as I'm contemplating using it in a future design.
Thanks,
Oscar |
This PIC family is a low cost single chip solution. Limitations with this PIC include:
relatively low amount of RAM available on the PIC for supporting network applications
relatively high current consumption for the Ethernet subsystem
limited to 10MHz Ethernet - this is not a performance limitation as this PIC family is not able to drive the Ethernet beyond 10MHz however there are some switch implementations that do not support 10MHz Ethernet
limited form factor choices
The Microchip stack consumes a proportionally large amount of the program memory space
The PIC32MX795 family is a "better" platform with respect to supporting 100MHz Ethernet, large, RAM and Program memory intensive applications however it requires an external phy and is therefore a two chip implementation and you still have to deal with limited form factors.
Another approach, one I use frequently, is to use a PIC24 family processor with an external ENC424J600 100MHz Ethernet controller. A two chip solution that addresses all limitations mentioned.
The PIC18F97J60 family remains the lowest cost single chip implementation. _________________ Regards, Andrew
http://www.brushelectronics.com/software
Home of Ethernet, SD card and Encrypted Serial Bootloaders for PICs!! |
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robleso7473
Joined: 25 Mar 2009 Posts: 47
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Posted: Thu Jun 30, 2011 5:25 am |
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Thank you for the feedback gentlemen.
All your points are understood.
Even with all the issues/drawbacks of this device I am not planning on
ever transmitting more than 100kB/sec of data across the network so I
don't want to incur the cost of a 10/100 device.
My application code can be condensed to less than 10K so a 128KB '67J60(with much of it storing the stack) is still very attractive being a single chip.
My question was leaning more towards the history and bugs of these devices. I read somewhere that Microchip's TCP/IP stack had some bugs but those can be dealt with. I was thinking maybe someone knew more about the actual performance and reliability of the integrated 10Mbps PHY in the device. It just seems amazing to me that they crammed all of that into an 8-bit uC.
What worries me is when you see Microchip's WebSeminars on these devices the guy starts out with #1 on using dynamic variables then goes on to #2 on the "GET" form method and #3 on the "POST" method and he ends #3 saying that there's a few more coming on sending email and setting security(passwords and such) but #4 never appeared on the site. This leads me to believe that either the product wasn't selling well and no interest was shown from the customers or that the videos were too cheezy and they put an end to that. |
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