Re: 6702 chip

Looks to me like the seed value is EOR'd with the written odd value and 
only the counters for those bits are incremented.

Given a seed of 214 - 11010110

Writing 00000001 results in 11010111 and bits 5 & 3 do not count.

Writing 00000011 results in 11010101 and bit 5,3 & 1 do not count.

Writing 00001001 results in 11011111 and bit 3 now counts with a period 
of 8.

Writing 00100001 results in 11110111 and bit 4 now counts with a period 
of 3.

Rob


On 12/05/2012 10:42, William Levak wrote:
> On Sat, 12 May 2012, William Levak wrote:
>
>> I don't think it very likely that a chip the size of a 6702 can do an 
>> actual divide.
>
> Not divisions; simple counting circuits, the intervals as Kajtar Zsolt 
> described.
>
> Starting number, 214
>
> 128 toggled every 2 numbers
>  64 toggled every 5 numbers
>  16 toggled every number
>   4 toggled every 7 numbers
>   2 toggled every 3 numbers
>   1 toggled every 6 numbers
>
> The pattern repeats every 420 numbers. (I neglected that 14 and 60 
> have a common factor).
>
> Each operation affects only one bit, the whole chip would require 8 
> counting circuits and perhaps a couple registers.  The output would 
> require a latched register.
>
> This is from writing 0, followed by 1. Now that I have a formula, I 
> can test what other numbers might do.
>
>
> wlevak@sdf.lonestar.org
> SDF Public Access UNIX System - http://sdf.lonestar.org
>
>       Message was sent through the cbm-hackers mailing list


       Message was sent through the cbm-hackers mailing list