参数资料
型号: MC68HC05SB7
厂商: FREESCALE SEMICONDUCTOR INC
元件分类: 微控制器/微处理器
英文描述: 8-BIT, MROM, 2.1 MHz, MICROCONTROLLER, PDSO28
封装: MO-150, SSOP-28
文件页数: 132/170页
文件大小: 2161K
代理商: MC68HC05SB7
GENERAL RELEASE SPECIFICATION
August 27, 1998
MOTOROLA
16-BIT TIMER
MC68HC05SB7
10-2
REV 2.1
The basis of the capture/compare Timer is a 16-bit free-running counter which
increases in count with each internal bus clock cycle. The counter is the timing ref-
erence for the input capture and output compare functions. The input capture and
output compare functions provide a means to latch the times at which external
events occur, to measure input waveforms, and to generate output waveforms and
timing delays. Software can read the value in the 16-bit free-running counter at
any time without affect the counter sequence.
Because of the 16-bit timer architecture, the I/O registers for the input capture and
output compare functions are pairs of 8-bit registers. Each register pair contains
the high and low byte of that function. Generally, accessing the low byte of a spe-
cic timer function allows full control of that function; however, an access of the
high byte inhibits that specic timer function until the low byte is also accessed.
Because the counter is 16 bits long and preceded by a xed divide-by-four pres-
caler, the counter rolls over every 262,144 internal clock cycles. Timer resolution
with a 4 MHz crystal oscillator is 2 microsecond/count.
The interrupt capability, the input capture edge, and the output compare state are
controlled by the timer control register (TCR) located at $0012 and the status of
the interrupt ags can be read from the timer status register (TSR) located at
$0013.
10.1
TIMER REGISTERS (TMRH, TMRL)
The functional block diagram of the 16-bit free-running timer counter and timer
registers is shown in Figure 10-2. The timer registers include a transparent buffer
latch on the LSB of the 16-bit timer counter.
Figure 10-2. Programmable Timer Block Diagram
T
OIE
TMRH ($0018)
TMR LSB
16-BIT COUNTER
÷ 4
INTERNAL
(fOSC ÷ 2)
TIMER CONTROL REG.
TIMER
REQUEST
OVERFLOW (TOF)
RESET
CLOCK
INTERRUPT
TMRL ($0019)
TO
F
TIMER STATUS REG.
$0012
$0013
INTERNAL
($FFFC)
DATA
READ
TMRH
READ
TMRL
READ
LATCH
BUS
相关PDF资料
PDF描述
MC68HC705SB7 8-BIT, OTPROM, 2.1 MHz, MICROCONTROLLER, PDSO28
MC68HC05SU3AB 8-BIT, MROM, 2 MHz, MICROCONTROLLER, PDIP42
MC68HC05T2P 8-BIT, MROM, MICROCONTROLLER, PDIP40
MC68HC08AS32CFN 8-BIT, EEPROM, 8.4 MHz, MICROCONTROLLER, PQCC52
MC68HC08AS32VFN 8-BIT, EEPROM, 8.4 MHz, MICROCONTROLLER, PQCC52
相关代理商/技术参数
参数描述
MC68HC05SC24 制造商:MOTOROLA 制造商全称:Motorola, Inc 功能描述:Secure 8-bit microcomputer with EEPROM
MC68HC05SR3 制造商:FREESCALE 制造商全称:Freescale Semiconductor, Inc 功能描述:High-density Complementary Metal Oxide Semiconductor (HCMOS) Microcontroller Units
MC68HC05SU3A 制造商:FREESCALE 制造商全称:Freescale Semiconductor, Inc 功能描述:Fully static chip design featuring the industry standard 8-bit M68HC05 core
MC68HC05T16 制造商:FREESCALE 制造商全称:Freescale Semiconductor, Inc 功能描述:High-density complementary metal oxide semiconductor (HCMOS) microcontroller unit
MC68HC05V12 制造商:FREESCALE 制造商全称:Freescale Semiconductor, Inc 功能描述:HCMOS Microcontreller Unit