8XC196MC, MD, MH USER’S MANUAL

numbers

Hexadecimal numbers are represented by a string of hexadecimal

 

digits followed by the character H. Decimal and binary numbers are

 

represented by their customary notations. (That is, 255 is a decimal

 

number and 1111 1111 is a binary number. In some cases, the letter B

 

is appended to binary numbers for clarity.)

register bits

Bit locations are indexed by 7:0 (or 15:0), where bit 0 is the least-

 

significant bit and bit 7 (or 15) is the most-significant bit. An

 

individual bit is represented by the register name, followed by a

 

period and the bit number. For example, WSR.7 is bit 7 of the

 

window selection register. In some discussions, bit names are used.

register names

Register mnemonics are shown in upper case. For example, TIMER2

 

is the timer 2 register; timer 2 is the timer. A register name containing

 

a lowercase italic character represents more than one register. For

 

example, the x in Px_REG indicates that the register name refers to

 

any of the port data registers.

reserved bits

Certain bits are described as reserved bits. In illustrations, reserved

 

bits are indicated with a dash (—). These bits are not used in this

 

device, but they may be used in future implementations. To help

 

ensure that a current software design is compatible with future imple-

 

mentations, reserved bits should be cleared (given a value of “0”) or

 

left in their default states, unless otherwise noted. Do not rely on the

 

values of reserved bits; consider them undefined.

signal names

Signal names are shown in upper case. When several signals share a

 

common name, an individual signal is represented by the signal name

 

followed by a number. For example, the EPA signals are named

 

EPA0, EPA1, EPA2, etc. Port pins are represented by the port abbre-

 

viation, a period, and the pin number (e.g., P1.0, P1.1); a range of

 

pins is represented by Px.y:z (e.g., P1.4:0 represents five port pins:

 

P1.4, P1.3, P1.2, P1.1, P1.0). A pound symbol (#) appended to a

 

signal name identifies an active-low signal.

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Intel 8XC196MD, 8XC196MH, 8XC196MC manual Numbers