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.