[Coco] Battery-Backed RTCs for CoCo?

[RETRO Innovations]

On 11/30/2018 5:51 PM, Dave Philipsen wrote:
> Actually we have a NitrOS9 driver for the newer (and cheaper) DS3231 
> chip that is so prevalent on many RTC boards available on eBay.  It is 
> currently used on the CoCo3FPGA.  I believe that the general register 
> architecture of the Dallas Semi chips are all pretty much the same.  
> It's just that the older ones were accessed in a slightly different 
> way before the advent of I2C and SPI.

Hmm, that one is still highly expensive, givent eh otehr I2C options on 
digikey.  And, the 400KHz max clock is a bummer, as that means I cannot 
interface it with the CoCo bus directly...