TMS370CX32 Datasheet, PDF (11/43 Pages) Texas Instruments – 8-BIT MICROCONTROLLER

TMS370Cx32
8-BIT MICROCONTROLLER
SPNS015C – FEBRUARY 1990 – REVISED FEBRUARY 1997
system reset (continued)
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ _REGISTER
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ _SCCR0
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ _SCCR0
ADDRESS
1010h
1010h
PF
P010
P010
Table 6. Reset Sources
BIT NO.
7
4
CONTROL BIT
COLD START
OSC FLT FLAG
SOURCE OF RESET
Cold (power-up)
Oscillator out of range
Once a reset is activated, the following sequence of events occurs:
1. The CPU registers are initialized: ST = 00h, SP = 01h (reset state).
2. Registers A and B are initialized to 00h (no other RAM is changed).
3. The contents of the LSbyte of the reset vector (07FFh) are read and stored in the PCL.
4. The contents of the MSbyte of the reset vector (07FEh) are read and stored in the PCH.
5. Program execution begins with an opcode fetch from the address pointed to the PC.
The reset sequence takes 20 SYSCLK cycles from the time the reset pulse is released until the first opcode
fetch. During a reset, RAM contents (except for registers A and B) remain unchanged, and the module control
register bits are initialized to their reset state.
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