4 ms·
Read the official manual - PDP-11/40 Processor Handbook. https://pdos.csail.mit.edu/6.828/2005/readings/pdp11-40.pdf https://pdos.csail.mit.edu/6.828/2005/read
by segfaultbuserr 6y ago
Read the official manual - PDP-11/40 Processor Handbook.
https://pdos.csail.mit.edu/6.828/2005/readings/pdp11-40.pdf https://pdos.csail.mit.edu/6.828/2005/readings/pdp11-40.pdf
The PDP-11 instruction set is small and elegant.
- Shared404 6y agoFrom the manual: > The PDP-11/40 was designed to fit a broad range of applications, from small stand alone situations ... to large multi-user, multi-task applications requiring up to 124K of addressable memory space. I'm young, and it's crazy to look back and see how far we've come.
- tyingq 6y agoFor some context, the PDP-11/40 debuted in 1973, and was $40k in 1973 dollars which is $233k inflation adjusted for today. There wasn't much available for a "home computer" at the time, but the Kenbak-1 might be a good example for comparison of what one would have cost. It was $750, or $4400 inflation adjusted. It had 256 bytes of memory.
- gjvnq 6y ago> The PDP-11 instruction set is small and elegant. Scared PDP-endianess sounds...
- freeone3000 6y agoIt's little-endian, same as x86.
- tomatocracy 6y agoI thought on the PDP-11 bytes in a 16 bit word were stored little endian but the 16 bit words in a 32 bit long were stored the other way around so it's a bit of both?
- userbinator 6y agoWords are little-endian but the two halves of a long are big-endian. In consistently little-endian, a 32-bit quantity would be stored with the 1's, 256's, 65536's, and 16777216's place bytes in that order, but the PDP-11 puts them in the order 65536 16777216 1 256.
- deleted 6y ago[deleted]