Instruction manual

12
Firmware: Overview
DEC 3000 firmware consists of these elements:
• Power-up initialization code (Section 12.1)
• A console program (Section 12.2)
• Extended self-test code and utilities (Section 12.3)
• Privileged architecture library code (PALcode) (Section 12.4)
• A MIPS Emulator (Section 12.5)
The firmware of all DEC 3000 models conforms to the description in this section
with these differences:
• Memory Subsytem
Each bank is comprised of one side of two 32-bit data SIMMs.
• In 300 models, a pair of single-sided SIMMs makes one 64-bit bank, while
a pair of double-sided SIMMs provides two 64-bit banks.
• In 400/500/600/700/800/900 models, a set of eight single-sided SIMMs
makes one 256-bit bank, while a set of eight double-sided SIMMs yields
two 256-bit banks.
Table 43 lists the memory differences among the models.
Table 43 Memory Differences
System
Max. Logical
Banks Data Path Width Protection
300 Models 8 64 bits Parity
400/600/700 4 256 bits ECC
500/800/900 8 256 bits ECC
• TURBOchannel
Refer to Table 9 and Table 10 for differences in I/O and hardware addresses.
Table 44 lists other TURBOchannel differences.
Firmware: Overview 12–1