Byte sizes (was Re: 2.8M 3.5' floppy
woodelf
bfranchuk at jetnet.ab.ca
Mon Mar 14 20:50:29 CST 2005
William Donzelli wrote:
>>The real gotya on the old machines... UPPER CASE ASCII ONLY.
>>
>>
>
>Actually, the switch to the eight bit byte (I am of the camp that a byte
>is 8 bits by default, then adjust to suit) was dictated not by characters,
>but by numbers - the vast majority of data in the 1960s was BCD. Six bit
>is not very efficient for handling BCD.
>
>
Umm 6 bits is perfect for BCD, look at IBM's 1620 : 4 bits BCD, 1 bit
sign flag/length flag 1 bit parity
The IBM 360 and I think marketing ... bytes give you 4x bigger memory
size, 1/4 the cost and
1/9 real $ savings over 36 bit words.
Ben alias woodelf
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