Studio Mintaka's CrissCross Cable

crisscross.txt

       _                  _           
      (_)       _        | |          
 ____  _ ____ _| |_ _____| |  _ _____ 
|    \| |  _ (_   _|____ | |_/ |____ | *
| | | | | | | || |_/ ___ |  _ (/ ___ | *
|_|_|_|_|_| |_| \__)_____|_| \_)_____| *
STUDIO MINTAKA : MANUFACTURER ID 0xABAD1DEA

  ___  ____  ____  ___  ___      ___  ____  _____  ___  ___ 
 / __)(  _ \(_  _)/ __)/ __)\ / / __)(  _ \(  _  )/ __)/ __)
( (__  )   / _)(_ \__ \\__ \ X ( (__  )   / )(_)( \__ \\__ \
 \___)(_)\_)(____)(___/(___// \ \___)(_)\_)(_____)(___/(___/
 "CRISSCROSS" CROSSOVER CABLE: ITEM ID 0xCC00CC00
 
 REVISION 0x0
 
 -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
 
 CRISSCROSS is a simple cable with a logic board that attaches two separate
 DCPU-16 systems and allows them to send and receive packets of 256 words.
 
 INTERRUPTS
 0 B - SETOUTGOING
 1 B - SETINCOMING
 2   - READY
 3   - RECEIVE
 
 
 Using it couldn't be simpler. First, make sure both computers are powered off,
 and securely connect both ends of the CRISSCROSS to their serial ports. 
 
 From within your software, call interrupt 0 (SETOUTGOING) with a pointer in
 register B to the 256-word region you wish the other end to be able to read
 from. This is your OUTGOING buffer.
 
 Next, call interrupt 1 (SETINCOMING) with a pointer in register B to the 256-
 word region that the other end will write into. This is your INCOMING buffer.
 
 Call interrupt 2 (READY) when you are currently not mucking around with your
 OUTGOING and it may be safely copied. The CRISSCROSS will immediately copy
 OUTGOING into its internal buffer on the logic board. 
 
 And whenever you want, call interrupt 3 (RECEIVE) to have the CRISSCROSS send
 you the other end's most recently READY'd OUTGOING into your INCOMING. If it
 has not changed, this will return immediately.
 
 Calling interrupt 2 without having called interrupt 0 will cause CRISSCROSS to
 store all zeroes. Calling interrupt 3 without having called interrupt 1 will
 result in no data being written to your RAM.
 
 If the other end calls interrupt 3 before you have set your OUTGOING, it will
 RECEIVE all zeroes.
 
 SETOUTCOMING and SETINCOMING may be raised at any time to change your current
 buffer locations. 
 
 
  -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
 Coming soon: the MINTAKA CLOVERWHEEL star topology router and the MINTAKA
 GREENBANK radio tranceiver!
 
 by Abigail van der Polder, STUDIO MINTAKA
 
extracanonical:
actually by Melissa 
@0xabad1dea / abadidea on freenode & reddit