M32C80 datasheet(49/352 Pages) RENESAS

49 / 352 page

Page 30

5. Reset

Hardware reset 1, software reset, and watchdog timer reset are available to reset the microcomputer.

5.1 Hardware Reset 1

____________

Pins, the CPU and SFRs are reset by setting the RESET pin. If the supply voltage meets the recommended

___________

operating conditions, all pins are reset when a low-level ("L") signal is applied to the RESET pin (see Table

5.1). The oscillation circuit is also reset and the main clock starts oscillating. The CPU and SFR are reset

____________

when the signal applied to the RESET pin changes "L" to high level ("H"). The microcomputer executes the

program in an address indicated by the reset vector. The internal RAM is not reset. When an "L" signal is

____________

applied to the RESET pin while writing data to the internal RAM, the internal RAM is in an indeterminate

state.

Figure 5.1 shows an example of the reset circuit. Figure 5.2 shows a reset sequence. Table 5.1 lists pin

____________

states while the RESET pin is held "L".

5.1.1 Reset on a Stable Supply Voltage

____________

(1) Apply an "L" signal to the RESET pin

(2) Provide 20 or more clock cycle inputs into the XIN pin

____________

(3) Apply an "H" signal to the RESET pin

5.1.2 Power-on Reset

____________

(1) Apply an "L" signal to the RESET pin

(2) Raise the supply voltage to the recommended operating level

(3) Insert

td(P-R) ms as wait time for the internal voltage to stabilize

(4) Provide 20 or more clock cycle inputs into the XIN pin

____________

(5) Apply an "H" signal to the RESET pin

Figure 5.1 Reset Circuit

RESET

VCC1

RESET

VCC1

Recommended

operating voltage

0.2VCC1 or below

0.2VCC1

or below

NOTE:

1. If VCC1>VCC2, the VCC2 voltage must be lower than that of VCC1 when the power is

being turned on or off.

td(P-R) + 20 or more clock cycle

inputs provided into the XIN pin

M32C80 Datasheet(PDF) 49 Page - Renesas Technology Corp

M32C80 Datasheet(HTML) 49 Page - Renesas Technology Corp

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL