RTL8019AS clock question

Hello all,

   The data sheet for the RTL8019AS is a bit vague about the clock
requirments. After emailing realtek and waiting a week for a response
they answered most of my questions (20MHz, 16pF load impedence,
<+-50ppm accuracy etc.) What they failed to answer is the voltage level
required from the oscillator. Does anyone know if a 5V output
oscillator will kill the X1 pin?

While I am here, I have one more quick question. Does the RTL8019AS
have internal logic that enables me to avoid glue logic between the
RTL8019AS and an EISA bus?

Thank you in advance for your help,
Matt

Matt wrote:
> Hello all,
> 
>    The data sheet for the RTL8019AS is a bit vague about the clock
> requirments. After emailing realtek and waiting a week for a response
> they answered most of my questions (20MHz, 16pF load impedence,
> <+-50ppm accuracy etc.) What they failed to answer is the voltage level
> required from the oscillator. Does anyone know if a 5V output
> oscillator will kill the X1 pin?

I've run thousands and thousands of RTL8019AS's
from the output of a Cypress CY2292F with no
problems.

> While I am here, I have one more quick question. Does the RTL8019AS
> have internal logic that enables me to avoid glue logic between the
> RTL8019AS and an EISA bus?

Yup.  Original application for the part was a
1 chip + EEPROM EISA ethernet controller.  You
can probably still find one on ebay or at a
surplus shop.

> Thank you in advance for your help,
> Matt
> 

Jim Stewart wrote:
> Matt wrote:
> > Hello all,
> >
> >    The data sheet for the RTL8019AS is a bit vague about the clock
> > requirments. After emailing realtek and waiting a week for a response
> > they answered most of my questions (20MHz, 16pF load impedence,
> > <+-50ppm accuracy etc.) What they failed to answer is the voltage level
> > required from the oscillator. Does anyone know if a 5V output
> > oscillator will kill the X1 pin?
>
> I've run thousands and thousands of RTL8019AS's
> from the output of a Cypress CY2292F with no
> problems.
>
> > While I am here, I have one more quick question. Does the RTL8019AS
> > have internal logic that enables me to avoid glue logic between the
> > RTL8019AS and an EISA bus?
>
> Yup.  Original application for the part was a
> 1 chip + EEPROM EISA ethernet controller.  You
> can probably still find one on ebay or at a
> surplus shop.
>
> > Thank you in advance for your help,
> > Matt
> >

Jim,

  Thank you for the quick reply.

> Yup.  Original application for the part was a
> 1 chip + EEPROM EISA ethernet controller.

What was the purpose of the EEPROM EISA ethernet controller? I am a bit
new to the old EISA bus (DAMN YOU VMEs!!!). If I plan on using the
jumpers instead of BROMs I dont understand the purpose of the extra
chip.

Thank you again,
Matt

Matt wrote:

> What was the purpose of the EEPROM EISA ethernet controller? I am a bit
> new to the old EISA bus (DAMN YOU VMEs!!!). If I plan on using the
> jumpers instead of BROMs I dont understand the purpose of the extra
> chip.

It contains the MAC address:

http://en.wikipedia.org/wiki/MAC_address

And stuff like base I/O port address,
interrupt and bus size.  Also a bunch
of plug and play registers I've never
fiddled with.