🚀 go-pugleaf

In article <721308024.4228@minster.york.ac.uk> mhw@minster.york.ac.uk 
writes:

>Can someone tell me the part number of the real time clock/non-volatile
>RAM chip used in the A3xx and A4xx series machines and suggest where I
>might be able to get hold of data sheets from? Are the same parts used
>in the newer machines (i.e. A5000 and co.)?

Its a PCF 8583 and it comes from Philips, at least the data book I have does.  
The whole IIC chipset fills two hefty volumes and includes some quite 
remarkable devices.  It makes fascinating reading.  I have done a bit of work 
driving IIC from my Model B if you ever want 6502 code to do it! 

I am interested by the suggestion made recently in this news group, that this chip 
may have a mode where it becomes an 'engine hours' counter rather than a RTC.  
I have a customer who is reporting exactly these symptoms for his machine I 
will be rather pleased if I can find a soft fix.  Power on R sounds like a good 
start.  I am going home to night to read the data book!

I think that its the same chip in all machines ( except being in an smd pack these 
days) , the A4 loads a different IIC module so that may be the odd one out.

Alan.
 
The views expressed are my own and are not necessarily those of Acorn.