8008 > IntelD8008

Modified: April 10, 2005, 6:44 pm

Manufacturer:	Intel
Model:	D8008
Speed:	500KHz
Type:	8008
Data Code:	8319
Introduced:	1972
Transistors:	3500
Package:	18CDIP
Process:	10 Micron
Architecture:	8 bit
Used in:	Intellec 8 and some IMSAI
Description:	The first 8-bit microprocessor, Intel 8008 was released 5 months after Intel 4004 microprocessor. The 8008 was available in two speed grades - 500 KHz and 800 KHz, but even the faster version 8008-1 was running a bit slower (in instructions per second) than the 4004. Nevertheless, overall performance of the 8008 was greater due to 8-bit architecture. The 8008 had other advantages over the 4004: Support of 16 KB of memory (ROM and RAM combined). Deeper stack: 7 levels instead of 3 levels. Interrupt capability. One of the drawbacks of the Intel 8008 was the absence of direct memory addressing. To access data in memory the memory address had to be stored in H and L registers, and only then the processor could indirectly access the memory. This limitation was removed in Intel 8080.