PT AMC131, Руководство по оборудованию

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Chapter 7
Programmable Registers
Several registers control and monitor a variety of functions on the AMC131. Normally, only the
system boot PROM uses these registers, but they are documented here for application use as
needed. Take care when modifying the contents of these registers: the system boot PROM
may be relying on the state of the bits under their control.
Key topics in this chapter:
• “Register Definitions,” on page 83
• “Custom Register Summary,” on page 83
Register Definitions
The following conventions are used throughout this document.
• IPMB, SMBus, and I2C addresses as transmitted on the bus are 7-bit values. By convention,
however, these addresses are listed as 8-bit values with the address in the upper 7 bits and a 0 in the
least significant bit (the R/~W bit).
• All signal names use the signal name convention of using the “_N” symbol at the end of a signal
name to indicate that the signal’s active state occurs when it is at a low voltage. The absence of the
“_N” or “n” symbol indicates that the signal is active high. Differential signals utilize _N and _P to
indicate polarity.
• Binary numbers are represented by a lower case ‘b’ suffix. For example, 1010b.
• Hexadecimal numbers are represented by a lower case ‘h’ suffix. All hex letters A-F are written in
uppercase. For example, 80BAh.
Custom Register Summary
The AMC131 features 24 custom registers. RO indicates that the field has read-only access.
RW indicates that the field has read/write access. WO indicates that the field has write-only
access. Some fields autoclear to their reset value and they are noted where applicable.
The following applies to the tables below that provide information about the custom register
bits:
• Register bits reset by a soft reset are also reset by a hard reset or power reset. Writable fields reset
by a soft. hard, or power reset are indicated by an S following the reset value.
• Register bits reset by a hard reset are also reset by a power reset. Writable fields reset by a hard or
power reset are indicated by an H following the reset value.
• Register bits reset by a power reset are only reset by a power reset. Writable fields reset only by a
power reset are indicated by a P following the reset value.
• Values in parenthesis indicate reset values.