參數(shù)資料
型號(hào): MC9RS08KA1CPC
廠商: FREESCALE SEMICONDUCTOR INC
元件分類: 微控制器/微處理器
英文描述: 8-BIT, FLASH, 20 MHz, MICROCONTROLLER, PDIP8
封裝: ROHS COMPLIANT, PLASTIC, DIP-8
文件頁數(shù): 5/136頁
文件大小: 2792K
代理商: MC9RS08KA1CPC
Chapter 12 Development Support
MC9RS08KA2 Series Data Sheet, Rev. 4
102
Freescale Semiconductor
Figure 12-5. BDM Target-to-Host Serial Bit Timing (Logic 0)
12.3.3
SYNC and Serial Communication Timeout
The host initiates a host-to-target serial transmission by generating a falling edge on the BKGD pin. If
BKGD is kept low for more than 128 target clock cycles, the target understands that a SYNC command
was issued. In this case, the target will keep waiting for a rising edge on BKGD to answer the SYNC
request pulse. If the rising edge is not detected, the target will keep waiting indefinitely, without any
timeout limit. When a rising edge on BKGD occurs after a valid SYNC request, the BDC will drive the
BKGD pin low for exactly 128 BDC cycles.
Consider now the case where the host returns BKGD to logic 1 before 128 cycles. This is interpreted as a
valid bit transmission, and not as a SYNC request. The target will keep waiting for another falling edge
marking the start of a new bit. If, however, a new falling edge is not detected by the target within 512 clock
cycles since the last falling edge, a timeout occurs and the current command is discarded without affecting
memory or the operating mode of the MCU. This is referred as a soft-reset to the BDC.
If a read command is issued but the data is not retrieved within 512 serial clock cycles, a soft-reset will
occur causing the command to be disregarded. The data is not available for retrieving after the timeout has
occurred. A soft-reset is also used to end a READ_BLOCK or WRITE_BLOCK command.
The following describes the actual bit-time requirements for a host to guarantee logic 1 or 0 bit
transmission without the target timing out or interpreting the bit as a SYNC command:
To send a logic 0, BKGD must be kept low for a minimum of 12 BDC cycles and up to 511 BDC
cycles except for the first bit of a command sequence, which will be detected as a SYNC request.
To send a logic 1, BKGD must be held low for at least four BDC cycles, be released by the eighth
cycle, and be held high until at least the sixteenth BDC cycle.
10 CYCLES
BDC CLOCK
(TARGET MCU)
HOST DRIVE
TO BKGD PIN
TARGET MCU
DRIVE AND
PERCEIVED START
OF BIT TIME
HIGH IMPEDANCE
BKGD PIN
10 CYCLES
SPEEDUP PULSE
SPEEDUP
PULSE
EARLIEST START
OF NEXT BIT
HOST SAMPLES BKGD PIN
相關(guān)PDF資料
PDF描述
MC9RS08KA1CDB 8-BIT, FLASH, 20 MHz, MICROCONTROLLER, DSO6
MC9RS08KA4CTG 8-BIT, FLASH, 20 MHz, MICROCONTROLLER, PDSO16
MC9RS08KA4CPJ 8-BIT, FLASH, 20 MHz, MICROCONTROLLER, PDIP20
MC9RS08KA8CPG 8-BIT, FLASH, 20 MHz, MICROCONTROLLER, PDIP16
MC9RS08KB2CSC MICROCONTROLLER, PDSO8
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MC9RS08KA1CSC 功能描述:8位微控制器 -MCU 1K FLASH W/ ACMP 62 RAM RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時(shí)鐘頻率:50 MHz 程序存儲(chǔ)器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風(fēng)格:SMD/SMT
MC9RS08KA1CSCR 功能描述:8位微控制器 -MCU 1K FLASH W/ ACMP 62 RAM RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時(shí)鐘頻率:50 MHz 程序存儲(chǔ)器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風(fēng)格:SMD/SMT
MC9RS08KA1DB 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:Microcontrollers
MC9RS08KA1PC 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:Microcontrollers
MC9RS08KA1SC 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:Microcontrollers