參數(shù)資料
型號(hào): CD1284
廠商: Intel Corp.
英文描述: IEEE 1284-Compatible Parallel Interface Controller with Two High-Speed Asynchronous Serial Ports
中文描述: 符合IEEE 1284兼容并行接口控制器兩個(gè)高速異步串行端口
文件頁數(shù): 139/176頁
文件大小: 2255K
代理商: CD1284
IEEE 1284-Compatible Parallel Interface Controller
CD1284
Datasheet
139
7.7.6
Parallel Auxiliary Control Register
This register provides some special functions for the parallel data path and interrupt generation
circuitry. The upper two bits change the basic timing of the timers associated with the data pipeline.
Bit 5 can disable the stale data timer. Bit 0 overrides the Fair Share functions of the device (serial
and parallel channels).
Bits
Description
7:3
User-defined Interrupt Vector:
Host software can use these five bits for any purpose appropriate to the
application. In some cases, these bits might define the rest of a complete interrupt response vector (Motorola-
type systems). In the case of daisy-chain systems made up of multiple CD1284s, these bits define the device
number in the chain.
2:0
Interrupt Vector Type Code:
These bits are read/writable in the normal context. These bits are
don
t cares
.
Register Name: PACR
Register Description: Parallel Auxiliary Control
Access: Read/Write
Bit 7
Bit 6
ShrtTen
ShrtStal
8-Bit Hex Address: 3F
Default Value: 00
Bit 5
StaleOff
Bit 4
Bit 3
ClearTO
Bit 2
0
Bit 1
Bit 0
Unfair
FIFOlock
AsyncDMA
Bit
Description
7
ShrtTen:
This function shortens the Prescaler count cycle that generates the internal 10-
μ
s (based on a 25-
MHz system clock) clock for the stale data counter. This bit is cleared by RESET*. If set, the 10-
μ
s
ticks
of
the counter are generated every two CLKs; the normal period is one
tick
every 250 CLKs.
6
ShrtStal:
This function shortens the period of the stale data timer. The stale data timer includes a divide-by-
10 prescaler; setting this bit bypasses the prescaler function thus causing the stale data timer to count on
each 10-
μ
s clock
tick
.
If both ShrtTen and ShrtStal are set, the stale data timer counts on every other CLK.
5
StaleOff:
If set, this bit masks off the Stale Status bit. The inverse of this bit is AND
ed with the stale state
condition of the parallel channel to produce the stale status and disables OneChar and Stale as interrupt
sources. StaleOff is provided primarily for test and development purposes if slow movement of data into the
parallel port causes Stale and OneChar to always appear true.
4
FIFOlock:
The FIFOlock bit causes the FIFO to stop accepting data from the parallel channel state machine.
This action makes the FIFO appear full to the parallel port, thus causing it to enter the
busy
state. This
function is primarily intended for use in system testing to cause a timeout on the 1284 bus.
Setting this bit in ECP Forward mode may cause a stall condition event 35 because event 36 does not occur
until FIFOlock is cleared. The ECP mode host transfer recovery handshake sequence (from event 35 stall) is
supported and the byte transit discarded as required by the specification. This bit does not provide an
effective means to flow control the host.
3
Clear Timeout:
This bit is a reset bit for the timeout status latch logic. When toggled by software, the timeout
status in the PFSR is cleared; it may be left set to disable the Timeout status function. Note that if this bit is
left set, the OneChar interrupt condition will never become true because the OneChar interrupt logic uses the
timeout status to determine when the FIFO has become stale.
相關(guān)PDF資料
PDF描述
CD13002 NPN SILICON PLANAR EPITAXIAL, HIGH VOLTAGE FAST SWITCHING POWER TRANSISTOR
CD14538 CMOS DUAL PRECISION MONOSTABLE MULTIVIBRATOR
CD14538BMS CMOS Dual Precision Monostable Multivibrator
CD15B-15MB CD105B
CD105B CD105B
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
CD-12AFFM-QL8D01 功能描述:MIDDLE 制造商:amphenol ltw 系列:* 零件狀態(tài):在售 標(biāo)準(zhǔn)包裝:10
CD-12AFFM-QR8D01 功能描述:MIDDLE 制造商:amphenol ltw 系列:* 零件狀態(tài):在售 標(biāo)準(zhǔn)包裝:10
CD-12AMMM-QL8D01 功能描述:MIDDLE 制造商:amphenol ltw 系列:* 零件狀態(tài):在售 標(biāo)準(zhǔn)包裝:10
CD-12BFFA-LL7001 功能描述:MIDDLE 制造商:amphenol ltw 系列:* 零件狀態(tài):在售 標(biāo)準(zhǔn)包裝:10
CD-12BFFA-QL8SP0 功能描述:CONN PLUG FMALE 12POS CRIMP 制造商:amphenol ltw 系列:X-Lok 包裝:散裝 零件狀態(tài):在售 連接器類型:插頭,母型插口 針腳數(shù):12(數(shù)據(jù)) 外殼尺寸 - 插件:C 外殼尺寸,MIL:- 安裝類型:自由懸掛 端接:壓接 緊固類型:推挽式 朝向:帶標(biāo)記 侵入防護(hù):IP68 - 防塵,防水 外殼材料,鍍層:聚酰胺(PA),尼龍,玻璃纖維增強(qiáng)型 觸頭鍍層:金 特性:后殼,應(yīng)力消除 電壓 - 額定:- 額定電流:5A 觸頭鍍層厚度:- 工作溫度:-20°C ~ 80°C 標(biāo)準(zhǔn)包裝:1