參數(shù)資料
型號: ST92186B3BK
廠商: STMICROELECTRONICS
元件分類: 微控制器/微處理器
英文描述: 16-BIT, MROM, 24 MHz, MICROCONTROLLER, PDIP32
封裝: PLASTIC, SDIP-32
文件頁數(shù): 123/148頁
文件大小: 1664K
代理商: ST92186B3BK
Obsolete
Product(s)
- Obsolete
Product(s)
Obsolete
Product(s)
- Obsolete
Product(s)
76/148
ST92186B - STANDARD TIMER (STIM)
STANDARD TIMER (Cont’d)
7.2.2 Functional Description
7.2.2.1 Timer/Counter control
Start-stop Count. The ST-SP bit (STC.7) is used
in order to start and stop counting. An instruction
which sets this bit will cause the Standard Timer to
start counting at the beginning of the next instruc-
tion. Resetting this bit will stop the counter.
If the counter is stopped and restarted, counting
will resume from the value held at the stop condi-
tion, unless a new constant has been entered in
the Standard Timer registers during the stop peri-
od. In this case, the new constant will be loaded as
soon as counting is restarted.
A new constant can be written in STH, STL, STP
registers while the counter is running. The new
value of the STH and STL registers will be loaded
at the next End of Count condition, while the new
value of the STP register will be loaded immedi-
ately.
Warning: In order to prevent incorrect counting of
the Standard Timer,the prescaler (STP) and counter
(STL, STH) registers must be initialised before the
starting of the timer. If this is not done, counting will
start with the reset values (STH=FFh, STL=FFh,
STP=FFh).
Single/Continuous Mode.
The S-C bit (STC.6) selects between the Single or
Continuous mode.
SINGLE MODE: at the End of Count, the Standard
Timer stops, reloads the constant and resets the
Start/Stop bit (the user programmer can inspect
the timer current status by reading this bit). Setting
the Start/Stop bit will restart the counter.
CONTINUOUS MODE: At the End of the Count, the
counter automatically reloads the constant and re-
starts.ItisonlystoppedbyresettingtheStart/Stopbit.
The S-C bit can be written either with the timer
stopped or running. It is possible to toggle the S-C
bit and start the Standard Timer with the same in-
struction.
7.2.3 Interrupt Selection
The Standard Timer may generate an interrupt re-
quest at every End of Count.
Bit 2 of the STC register (INTS) selects the inter-
rupt source between the Standard Timer interrupt
and the external interrupt pin. Thus the Standard
Timer Interrupt uses the interrupt channel and
takes the priority and vector of the external inter-
rupt channel.
If INTS is set to “1”, the Standard Timer interrupt is
disabled; otherwise, an interrupt request is gener-
ated at every End of Count.
Note: When enabling or disabling the Standard
Timer Interrupt (writing INTS in the STC register)
an edge may be generated on the interrupt chan-
nel, causing an unwanted interrupt.
To avoid this spurious interrupt request, the INTS
bit should be accessed only when the interrupt log-
ic is disabled (i.e. after the DI instruction). It is also
necessary to clear any possible interrupt pending
requests on the corresponding external interrupt
channel before enabling it. A delay instruction (i.e.
a NOP instruction) must be inserted between the
reset of the interrupt pending bit and the INTS
write instruction.
7.2.4 Register Mapping
Depending on the ST9 device there may be up to 4
Standard Timers (refer to the block diagram in the
first section of the data sheet).
Each Standard Timer has 4 registers mapped into
Page 11 in Group F of the Register File
In the register description on the following page,
register addresses refer to STIM0 only.
STD Timer Register
Register Address
STIM
STH0
R240 (F0h)
STL0
R241 (F1h)
STP0
R242 (F2h)
STC0
R243 (F3h)
相關PDF資料
PDF描述
ST92195B2T1/XXX 16-BIT, MROM, 24 MHz, MICROCONTROLLER, PQFP64
ST92195B3B1/XXX 16-BIT, MROM, 24 MHz, MICROCONTROLLER, PDIP56
ST92195B4B1/XXX 16-BIT, MROM, 24 MHz, MICROCONTROLLER, PDIP56
ST92195B5T1/XXX 16-BIT, MROM, 24 MHz, MICROCONTROLLER, PQFP64
ST92195B6T1/XXX 16-BIT, MROM, 24 MHz, MICROCONTROLLER, PQFP64
相關代理商/技術參數(shù)
參數(shù)描述
ST92195 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:32-64K ROM HCMOS MCU WITH ON-SCREEN-DISPLAY AND TELETEXT DATA SLICER
ST92195B 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:32-64K ROM HCMOS MCU WITH ON-SCREEN-DISPLAY AND TELETEXT DATA SLICER
ST92195B1 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:32-64K ROM HCMOS MCU WITH ON-SCREEN-DISPLAY AND TELETEXT DATA SLICER
ST92195B1B1 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:32-64K ROM HCMOS MCU WITH ON-SCREEN-DISPLAY AND TELETEXT DATA SLICER
ST92195B1T1 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:32-64K ROM HCMOS MCU WITH ON-SCREEN-DISPLAY AND TELETEXT DATA SLICER