TMP92CF30
2009-06-12
92CF30-13
3.1.2
Reset Operation
When resetting the TMP92CF30 microcontroller, ensure that the power supply voltage is
within the operating voltage range, and that the internal high-frequency oscillator has
stabilized. Then hold the
RESET
input Low for at least 20 system clocks (32µs at
X1=10MHz).
At reset, since the clock doublers (PLL0) is bypassed and the clock-gear is set to 1/16, the
system clock operates at 625 kHz(X1=10MHz).
When the Reset has been accepted, the CPU performs the following. CPU internal
registers do not change when the Reset is released.
•
Sets the Stack Pointer (XSP) to 00000000H.
•
Sets bits <IFF2:0> of the Status Register (SR) to “111” (thereby setting the Interrupt Level
Mask Register to level 7).
•
Clears bits <RFP1:0> of the Status Register to “00” (thereby selecting Register Bank 0).
When the Reset is released, the CPU starts executing instructions according to the
Program Counter settings.
•
Sets the Program Counter (PC) as follows in accordance with the Reset Vector stored at
address FFFF00H~FFFF02H:
PC<7:0>
←
data in location FFFF00H
PC<15:8>
←
data in location FFFF01H
PC<23:16>
←
data in location FFFF02H
When the Reset is accepted, the CPU sets internal I/O, ports and other pins as follows.
•
Initializes the internal I/O registers as table of “Special Function Register” in Section 5.
Figure 3.1.1 shows reset timing chart. Figure 3.1.2 shows the example of order of
supplying power and the timing of releasing reset.
Note: This LSI builds in RAM internally. However, the data in internal RAM may not be held by Reset operation. After
reset, initialize the data in internal RAM.
Summary of Contents for TLCS-900/H1 Series
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