Finally: Broadband for the Commodore 64

GP writes "Now even die-hard Commodore 64 users are able to enjoy the benefits of broadband Internet connectivity. A newly announced Ethernet card together with the Contiki operating system lets you surf the web, send e-mail, host web sites with the built-in web server, and soon even play LAN games on your good old Commodore 64! All this with a computer that is old enough to drink."

Comments

Re:Uhmm..

[Nos.]

Well, in some countries there is a minimum age to purchase alcohol. In the US, its 21. According to: http://oldcomputers.net/c64.html the commodore was released Jan, 1982. Making it 21 years old, or, old enough to drink.

Re:But can it fill 10BaseT?

[ewhac]

So...can it [flood a 10BaseT network]?

No. It can't.

If not, how much traffic do I have to send it to bring it to a crawl? :-)

Not much, I would think.

The C64 has a 1MHz 6510 8-bit CPU. The memory bus is also 1MHz. Moreover, the fastest instruction on the 6510 (which is a 6502 derivative) is two clocks. Thus, at four clocks per byte (two to read, two to write), the fastest data transfer rate you could conceivably get is 0.25 MBytes/second (in reality, it would be rather slower as the LDA and STA instructions take more than two clocks, but I don't have the timing chart in front of me).

The C64 does have DMA, but it's dedicated to video access and refresh and can't be redirected. Moreover, these DMA cycles completely take over the bus for 40 clocks every eight video lines. So your packet writes will likely hiccup from time to time. (Presumably they have big silos on the NIC.)

Even if the NIC did DMA itself, it would have to get out of video's way every eight lines, which means you couldn't flood the line indefinitely. Also, the C-64 has a mere -- surprise! -- 64K of RAM. At 1MByte/sec, you'd run out of RAM in 0.065536 seconds.

Schwab
C-64 Early Adopter