BUSICOM's project: Intel 4004 family
four chips (numbers then; pre "pentium" days; can't copyright numbers...):
- 4001 ROM with I/O (2000 bit ROM) adventurous project at this time;
required lots of external support electronics.
- 4002 RAM: 320bit (had output only registers)
- 4003 static 10 bit shift-register (simple ser. in, par. out device)
- 4004 CPU
the 4004 CPU:
- instruction set tailored for calculator applications:
- exclusive contract for BUSICOM.
- 2300 transistors
- crippled by a factor of 3 by being inside a 16 pin DIP.
- address and data multiplexed to 4 bits
- p-channel technology: +5v and -12v