Page 37
TMP89FM42
RA001
Figure 2-13 Switching the Main System Clock (fm) (Switching from fs/4 to fcgck)
Example : Switching from the SLOW1 mode to the NORMAL1 mode after the stability of the high-frequency clock oscilla-
tion circuit is confirmed at the warm-up counter (fc = 10 MHz, warm-up time = 4.0 ms)
; #### Initialize routine ####
SET
(P0FC).2
; P0FC2 = 1
(Uses P02/03 as oscillators)
¦
¦
LD
(WUCCR), 0x09
; WUCCR<WUCDIV> = 10 (Divided by 2)
WUCCR<WUCSEL> = 0 (Selects fc as the source clock)
LD
(WUCDR), 0x9D
; Sets the warm-up time
(Determine the time depending on the frequency and the oscillator
characteristics)
4ms / 25.6us = 156.25
→
round up to 0x9D
SET
(EIRL). 4
; Enables INTWUC interrupts
SET
(SYSCR2) .6
; SYSCR2<XEN> = 1
(Starts the oscillation of the high-frequency clock oscillation circuit)
¦
; #### Interrupt service routine of warm-up counter interrupts ####
PINTWUC:
CLR
(SYSCR2). 4
; SYSCR2<SYSCK> = 0
(Switches the main system clock to the gear clock)
NOP
; Waits for 2 machine cycles
NOP
CLR
(SYSCR2). 5
; SYSCR2<XTEN> = 0
(Turns off the low-frequency clock oscillation circuit)
RETI
¦
VINTWUC:
DW
PINTWUC
; INTWUC vector table
Gear clock (fcgck)
When the rising edge of fs/4 is
detected twice after SYSCR2<SYSCK>
is changed from 1 to 0, f is stopped
for synchronization.
When the rising edge of fcgck is detected
twice after fm is stopped, fm is switched to fcgck.
Quarter of the low-frequency clock
(fs/4)
Main system clock
SYSCR2<SYSCK>
2.5/fcgck(max.)
Summary of Contents for TLCS-870/C1 Series
Page 1: ...8 Bit Microcontroller TLCS 870 C1 Series TMP89FM42 查询TMP89FM42供应商 捷多邦 专业PCB打样工厂 24小时加急出货 ...
Page 3: ...Revision History Date Revision 2007 10 25 1 First Release 2007 11 3 2 Contents Revised ...
Page 4: ......
Page 14: ......
Page 18: ...1 3 Block Diagram TMP89FM42 1 3 Block Diagram Figure 1 2 Block Diagram ...
Page 22: ...1 4 Pin Names and Functions TMP89FM42 ...
Page 60: ...2 CPU Core 2 5 Revision History TMP89FM42 ...
Page 76: ...3 Interrupt Control Circuit 3 8 Revision History TMP89FM42 ...
Page 86: ...4 External Interrupt control circuit 4 3 Function TMP89FM42 ...
Page 102: ...7 Voltage Detection Circuit 7 5 Revision History TMP89FM42 ...
Page 126: ...8 I O Ports 8 3 I O Port Registers TMP89FM42 Note 2 i 0 to 1 ...
Page 136: ...8 I O Ports 8 5 Revision History TMP89FM42 ...
Page 142: ...9 Special Function Registers 9 3 SFR3 0x0E40 to 0x0EFF TMP89FM42 ...
Page 146: ...10 Low Power Consumption Function for Peripherals TMP89FM42 ...
Page 149: ...TMP89FM42 11 3 Revision History Rev Description RA001 Deleted SLEEP2 description ...
Page 150: ...11 Divider Output DVO 11 3 Revision History TMP89FM42 ...
Page 220: ...15 Real Time Clock RTC 15 4 Real Time Clock Operation TMP89FM42 ...
Page 250: ...16 Asynchronous Serial Interface UART 16 15 Revision History TMP89FM42 ...
Page 302: ...18 Serial Bus Interface SBI 18 7 Revision History TMP89FM42 ...
Page 338: ...21 Flash Memory 21 4 Toggle Bit D6 TMP89FM42 ...
Page 384: ...22 Serial PROM Mode 22 15 Revision History TMP89FM42 ...
Page 388: ...24 Input Output Circuit 24 1 Control Pins TMP89FM42 ...
Page 404: ...25 Electrical Characteristics 25 11 Revision History TMP89FM42 ...
Page 406: ...26 Package Dimensions TMP89FM42 ...
Page 408: ......