M37517F8HP Datasheet, PDF (54/98 Pages) Renesas Technology Corp – SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER

7517 Group
sNotes on middle-speed mode switch set bit
When the middle-speed mode automatic switch set bit is set to “1”
during operation in the low-speed mode, XIN oscillation starts au-
tomatically by detecting the rising edge or the falling edge of the
SCL pin or the SDA pin and the microcomputer switch to the
middle-speed mode. Select the timing which switch from the low-
speed mode to the middle-speed mode by the middle-speed mode
automatic switch wait time set bit. The timing which changes from
the low-speed mode by the middle-speed mode automatic switch
wait time set bit. Select according to the oscillation start character-
istic of the oscillator of XIN to be used. By writing “1” in the
middle-speed mode automatic switch start bit during operation in
the low-speed mode, XIN oscillation starts automatically and the
microcomputer changes to the middle-speed mode.
b7
b0
MISRG(003816)
Oscillation stabilizing time set after STP instruction
released bit
0: Automatically set “0116” to Timer 1, “FF16” to Prescaler
12
1: Automatically set nothing
Middle-speed mode automatic switch set bit
0: Disabled
1: Automatic switch enabled (Notes 1, 2)
Middle-speed mode automatic switch wait time set bit
0: 4.5 to 5.5 cycles
1: 6.5 to 7.5 cycles
Middle-speed mode automatic switch start bit
(depends on software)
0: Invalid
1: Automatic switch start (Note 2)
Not used (return “0” when read)
Notes 1: The microcomputer can be switched to the middle-speed mode automatically by the
SCL/SDA interrupt during operation in the low-speed mode.
2: When switching from the low-speed mode to the middle-speed mode, the value of the
CPU mode register also changes.
Fig.61 Structure of MISRG1, MISRG2
b7
b0
MISRG2(003716)
Analog in addtional bit
bit0 ADCON
(003416)
bit2 bit1 bit0
0
XXX
1
000
1
001
1
010
1
011
1
1 XX
P35/AN5 - P30/AN0
P04/AN8
P05/AN9
P06/AN10
P07/AN11
Not available
32kHz RC oscillation calibration enable bit (Note 4)
0:Disabled
1:Enabled
High-speed on-chip oscillation stop bit (Note 4)
0:Oscillating
1:Stopping
Xin swith disable bit (Notes 3, 4)
0:Enable swith to XIN
1:Disable swith to XIN
32kHz RC oscillation enable bit (Note 4)
0:XCIN-XCOUT oscillation
1:32kHz RC oscillation
Low-speed mode serial I/O2 clock source select bit
0:XCIN
1:Built-in oscillator for SI/O2
Not used (returnn"0" when read)
Reserved (do not write "1")
Notes 3: When this bit is set to "1", it cannot be rewritten to "0" by program.
4: This bit is protected.
b7
b0
b7 b6 b5 b4 b3 b2 b1 b0 ^{32kHz oscillation control register 0 (003216)}
b7
b0
b8 ^{32kHz oscillation control register 1 (003316)}
Fig.62 32kHz oscillation control register
Rev.1.01 Aug 02, 2004 page 54 of 96