參數(shù)資料
型號(hào): FN2969
廠商: Intersil Corporation
英文描述: CMOS Programmable Peripheral Interface
中文描述: CMOS可編程外設(shè)接口
文件頁數(shù): 5/26頁
文件大?。?/td> 233K
代理商: FN2969
5
The modes for Port A and Port B can be separately defined,
while Port C is divided into two portions as required by the
Port A and Port B definitions. All of the output registers,
including the status flip-flops, will be reset whenever the
mode is changed. Modes may be combined so that their
functional definition can be “tailored” to almost any I/O
structure. For instance: Group B can be programmed in
Mode 0 to monitor simple switch closings or display compu-
tational results, Group A could be programmed in Mode 1 to
monitor a keyboard or tape reader on an interrupt-driven
basis.
The mode definitions and possible mode combinations may
seem confusing at first, but after a cursory review of the
complete device operation a simple, logical I/O approach will
surface. The design of the 82C55A has taken into account
things such as efficient PC board layout, control signal defi-
nition vs. PC layout and complete functional flexibility to sup-
port almost any peripheral device with no external logic.
Such design represents the maximum use of the available
pins.
Single Bit Set/Reset Feature (Figure 5)
Any of the eight bits of Port C can be Set or Reset using a
single Output instruction. This feature reduces software
requirements in control-based applications.
When Port C is being used as status/control for Port A or B,
these bits can be set or reset by using the Bit Set/Reset
operation just as if they were output ports.
Interrupt Control Functions
When the 82C55A is programmed to operate in mode 1 or
mode 2, control signals are provided that can be used as
interrupt request inputs to the CPU. The interrupt request
signals, generated from port C, can be inhibited or enabled
by setting or resetting the associated INTE flip-flop, using the
bit set/reset function of port C.
This function allows the programmer to enable or disable a
CPU interrupt by a specific I/O device without affecting any
other device in the interrupt structure.
INTE Flip-Flop Definition
(BIT-SET)-INTE is SET - Interrupt Enable
(BIT-RESET)-INTE is Reset - Interrupt Disable
NOTE:
lection and device Reset.
All Mask flip-flops are automatically reset during mode se-
Operating Modes
Mode 0
(Basic Input/Output). This functional configuration
provides simple input and output operations for each of the
three ports. No handshaking is required, data is simply writ-
ten to or read from a specific port.
Mode 0 Basic Functional Definitions:
Two 8-bit ports and two 4-bit ports
Any Port can be input or output
Outputs are latched
Input are not latched
16 different Input/Output configurations possible
FIGURE 5. BIT SET/RESET FORMAT
D7 D6 D5
D4 D3 D2
D1 D0
BIT SET/RESET
1 = SET
0 = RESET
BIT SELECT
0
1 2 3 4 5 6 7
0 1 0 1 0 1 0 1
0 0 1 1 0 0 1 1
0 0 0 0 1 1 1 1
BIT SET/RESET FLAG
0 = ACTIVE
CONTROL WORD
DON’T
CARE
X
X
X
B0
B1
B2
MODE 0 PORT DEFINITION
A
B
GROUP A
#
GROUP B
D4
D3
D1
D0
PORT A
PORTC
(Upper)
PORT B
PORTC
(Lower)
0
0
0
0
Output
Output
0
Output
Output
0
0
0
1
Output
Output
1
Output
Input
0
0
1
0
Output
Output
2
Input
Output
0
0
1
1
Output
Output
3
Input
Input
0
1
0
0
Output
Input
4
Output
Output
0
1
0
1
Output
Input
5
Output
Input
0
1
1
0
Output
Input
6
Input
Output
0
1
1
1
Output
Input
7
Input
Input
1
0
0
0
Input
Output
8
Output
Output
1
0
0
1
Input
Output
9
Output
Input
1
0
1
0
Input
Output
10
Input
Output
1
0
1
1
Input
Output
11
Input
Input
1
1
0
0
Input
Input
12
Output
Output
1
1
0
1
Input
Input
13
Output
Input
1
1
1
0
Input
Input
14
Input
Output
1
1
1
1
Input
Input
15
Input
Input
82C55A
相關(guān)PDF資料
PDF描述
FN3138 5V High-Speed RS-232 Transceivers with 0.1uF Capacitors
FN4117A ULTRA-HIGH INPUT IMPEDANCE N-CHANNEL JFET
FN4496 Advanced PWM and Dual Linear Power Control
FN4819 Synchronous-Rectified Buck MOSFET Drivers
FN4819.1 Synchronous-Rectified Buck MOSFET Drivers
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
FN2-M3 制造商:JST Manufacturing 功能描述:
FN2-M5 制造商:JST Manufacturing 功能描述:
FN2T 功能描述:燈 LAMP W/50mm LEADS RoHS:否 制造商:Chicago Miniature 燈類型:Incandescent 燈座類型:Wire Terminal 燈大小:T-1 3/4 顏色: 電壓:14 V 工作電流: MSCP:0.3 MSCP 壽命:40000 hr 封裝:Bulk
FN2TB 功能描述:LAMP NEON T2 END TYPE WIRE BLUE RoHS:否 類別:光電元件 >> 燈 - 白熾燈,氖燈 系列:- 標(biāo)準(zhǔn)包裝:100 系列:- 顏色:透明 透鏡樣式/尺寸:圓形,帶圓頂,5mm,T-1 3/4 引線型:小型凹槽 MSCP(平均球面燭光):0.3 額定電壓:60V 其它名稱:913.4005913.4005-ND
FN3000035 功能描述:OSC 30MHZ 3.3V SMD RoHS:是 類別:晶體和振蕩器 >> 振蕩器 系列:SaRonix-eCera™ FN 標(biāo)準(zhǔn)包裝:1 系列:VG-4512CA 類型:VCXO 頻率:153.6MHz 功能:三態(tài)(輸出啟用) 輸出:LVPECL 電源電壓:3.3V 頻率穩(wěn)定性:- 工作溫度:-40°C ~ 85°C 電流 - 電源(最大):60mA 額定值:- 安裝類型:表面貼裝 尺寸/尺寸:0.276" L x 0.197" W(7.00mm x 5.00mm) 高度:0.071"(1.80mm) 封裝/外殼:6-SMD,無引線(DFN,LCC) 包裝:Digi-Reel® 電流 - 電源(禁用)(最大):- 其它名稱:SER3790DKR