参数资料
| 型号： | COP8CDR9LVA8 |
| 厂商： | National Semiconductor |
| 文件页数： | 86/111页 |
| 文件大小： | 0K |
| 描述： | IC MCU CMOS 8BIT 68-PLCC |
| 标准包装： | 18 |
| 系列： | COP8™ 8C |
| 核心处理器： | COP8 |
| 芯体尺寸： | 8-位 |
| 速度： | 20MHz |
| 连通性： | Microwire/Plus（SPI），UART/USART |
| 外围设备： | POR，PWM，WDT |
| 输入/输出数： | 59 |
| 程序存储器容量： | 32KB（32K x 8） |
| 程序存储器类型： | 闪存 |
| RAM 容量： | 1K x 8 |
| 电压 - 电源 (Vcc/Vdd)： | 2.7 V ~ 5.5 V |
| 数据转换器： | A/D 16x10b |
| 振荡器型： | 内部 |
| 工作温度： | -40°C ~ 85°C |
| 封装/外壳： | 68-LCC（J 形引线） |
| 包装： | 管件 |
| 其它名称： | *COP8CDR9LVA8 |
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SNOS535I – OCTOBER 2000 – REVISED MARCH 2013
5.15.3 VIS INSTRUCTION
The general interrupt service routine, which starts at address 00FF Hex, must be capable of handling all
types of interrupts. The VIS instruction, together with an interrupt vector table, directs the device to the
specific interrupt handling routine based on the cause of the interrupt.
VIS is a single-byte instruction, typically used at the very beginning of the general interrupt service routine
at address 00FF Hex, or shortly after that point, just after the code used for context switching. The VIS
instruction determines which enabled and pending interrupt has the highest priority, and causes an indirect
jump to the address corresponding to that interrupt source. The jump addresses (vectors) for all possible
interrupts sources are stored in a vector table.
The vector table may be as long as 32 bytes (maximum of 16 vectors) and resides at the top of the 256-
byte block containing the VIS instruction. However, if the VIS instruction is at the very top of a 256-byte
block (such as at 00FF Hex), the vector table resides at the top of the next 256-byte block. Thus, if the
VIS instruction is located somewhere between 00FF and 01DF Hex (the usual case), the vector table is
located between addresses 01E0 and 01FF Hex. If the VIS instruction is located between 01FF and 02DF
Hex, then the vector table is located between addresses 02E0 and 02FF Hex, and so on.
Each vector is 15 bits long and points to the beginning of a specific interrupt service routine somewhere in
the 32-kbyte memory space. Each vector occupies two bytes of the vector table, with the higher-order byte
at the lower address. The vectors are arranged in order of interrupt priority. The vector of the maskable
interrupt with the lowest rank is located to 0yE0 (higher-order byte) and 0yE1 (lower-order byte). The next
priority interrupt is located at 0yE2 and 0yE3, and so forth in increasing rank. The Software Trap has the
highest rand and its vector is always located at 0yFE and 0yFF. The number of interrupts which can
become active defines the size of the table.
Table 5-27 shows the types of interrupts, the interrupt arbitration ranking, and the locations of the
corresponding vectors in the vector table.
The vector table should be filled by the user with the memory locations of the specific interrupt service
routines. For example, if the Software Trap routine is located at 0310 Hex, then the vector location 0yFE
and -0yFF should contain the data 03 and 10 Hex, respectively. When a Software Trap interrupt occurs
and the VIS instruction is executed, the program jumps to the address specified in the vector table.
The interrupt sources in the vector table are listed in order of rank, from highest to lowest priority. If two or
more enabled and pending interrupts are detected at the same time, the one with the highest priority is
serviced first. Upon return from the interrupt service routine, the next highest-level pending interrupt is
serviced.
If the VIS instruction is executed, but no interrupts are enabled and pending, the lowest-priority interrupt
vector is used, and a jump is made to the corresponding address in the vector table. This is an unusual
occurrence and may be the result of an error. It can legitimately result from a change in the enable bits or
pending flags prior to the execution of the VIS instruction, such as executing a single cycle instruction
which clears an enable flag at the same time that the pending flag is set. It can also result, however, from
inadvertent execution of the VIS command outside of the context of an interrupt.
The default VIS interrupt vector can be useful for applications in which time critical interrupts can occur
during the servicing of another interrupt. Rather than restoring the program context (A, B, X, etc.) and
executing the RETI instruction, an interrupt service routine can be terminated by returning to the VIS
instruction. In this case, interrupts will be serviced in turn until no further interrupts are pending and the
default VIS routine is started. After testing the GIE bit to ensure that execution is not erroneous, the
routine should restore the program context and execute the RETI to return to the interrupted program.
This technique can save up to fifty instruction cycles (tC), or more, (25 s at 10 MHz oscillator) of latency
for pending interrupts with a penalty of fewer than ten instruction cycles if no further interrupts are
pending.
76
Functional Description
Copyright 2000–2013, Texas Instruments Incorporated
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| COP8CFE9 | 制造商:NSC 制造商全称:National Semiconductor 功能描述:8-Bit CMOS Flash Microcontroller with 8k Memory, Virtual EEPROM, and 10-Bit A/D |
| COP8CFE9HLQ9 | 功能描述:IC MCU FLASH 8BIT 8K A/D 44LLP RoHS:是 类别:集成电路 (IC) >> 嵌入式 - 微控制器， 系列:COP8™ 8C 标准包装:250 系列:56F8xxx 核心处理器:56800E 芯体尺寸:16-位 速度:60MHz 连通性:CAN，SCI，SPI 外围设备:POR，PWM，温度传感器，WDT 输入/输出数:21 程序存储器容量:40KB（20K x 16） 程序存储器类型:闪存 EEPROM 大小:- RAM 容量:6K x 16 电压 - 电源 (Vcc/Vdd):2.25 V ~ 3.6 V 数据转换器:A/D 6x12b 振荡器型:内部 工作温度:-40°C ~ 125°C 封装/外壳:48-LQFP 包装:托盘 配用:MC56F8323EVME-ND - BOARD EVALUATION MC56F8323 |
| COP8CFE9HVA9/NOPB | 功能描述:IC MCU EEPROM 8BIT 8K 44-PLCC RoHS:是 类别:集成电路 (IC) >> 嵌入式 - 微控制器， 系列:COP8™ 8C 标准包装:250 系列:56F8xxx 核心处理器:56800E 芯体尺寸:16-位 速度:60MHz 连通性:CAN，SCI，SPI 外围设备:POR，PWM，温度传感器，WDT 输入/输出数:21 程序存储器容量:40KB（20K x 16） 程序存储器类型:闪存 EEPROM 大小:- RAM 容量:6K x 16 电压 - 电源 (Vcc/Vdd):2.25 V ~ 3.6 V 数据转换器:A/D 6x12b 振荡器型:内部 工作温度:-40°C ~ 125°C 封装/外壳:48-LQFP 包装:托盘 配用:MC56F8323EVME-ND - BOARD EVALUATION MC56F8323 |
| COP8CFE9IMT9/NOPB | 功能描述:IC MCU EEPROM 8BIT 8K 48-TSSOP RoHS:是 类别:集成电路 (IC) >> 嵌入式 - 微控制器， 系列:COP8™ 8C 标准包装:250 系列:56F8xxx 核心处理器:56800E 芯体尺寸:16-位 速度:60MHz 连通性:CAN，SCI，SPI 外围设备:POR，PWM，温度传感器，WDT 输入/输出数:21 程序存储器容量:40KB（20K x 16） 程序存储器类型:闪存 EEPROM 大小:- RAM 容量:6K x 16 电压 - 电源 (Vcc/Vdd):2.25 V ~ 3.6 V 数据转换器:A/D 6x12b 振荡器型:内部 工作温度:-40°C ~ 125°C 封装/外壳:48-LQFP 包装:托盘 配用:MC56F8323EVME-ND - BOARD EVALUATION MC56F8323 |
| COP8CJ20 WAF | 制造商:Texas Instruments 功能描述: |
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