- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄368705 > 12C508A (Microchip Technology Inc.) Hookup/Lead Wire; Conductor Size AWG:18; No. Strands x Strand Size:65 x 36; Jacket Color:White; Conductor Material:Copper; Jacket Material:Rubber; Leaded Process Compatible:Yes; Number of Conductors:1; Outer Diameter:0.144" RoHS Compliant: Yes PDF資料下載
參數(shù)資料
| 型號(hào)： | 12C508A |
| 廠商： | Microchip Technology Inc. |
| 英文描述： | Hookup/Lead Wire; Conductor Size AWG:18; No. Strands x Strand Size:65 x 36; Jacket Color:White; Conductor Material:Copper; Jacket Material:Rubber; Leaded Process Compatible:Yes; Number of Conductors:1; Outer Diameter:0.144" RoHS Compliant: Yes |
| 中文描述： | 8引腳，8位CMOS微控制器 |
| 文件頁數(shù)： | 27/113頁 |
| 文件大?。?/td> | 1604K |
| 代理商： | 12C508A |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁第15頁第16頁第17頁第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁當(dāng)前第27頁第28頁第29頁第30頁第31頁第32頁第33頁第34頁第35頁第36頁第37頁第38頁第39頁第40頁第41頁第42頁第43頁第44頁第45頁第46頁第47頁第48頁第49頁第50頁第51頁第52頁第53頁第54頁第55頁第56頁第57頁第58頁第59頁第60頁第61頁第62頁第63頁第64頁第65頁第66頁第67頁第68頁第69頁第70頁第71頁第72頁第73頁第74頁第75頁第76頁第77頁第78頁第79頁第80頁第81頁第82頁第83頁第84頁第85頁第86頁第87頁第88頁第89頁第90頁第91頁第92頁第93頁第94頁第95頁第96頁第97頁第98頁第99頁第100頁第101頁第102頁第103頁第104頁第105頁第106頁第107頁第108頁第109頁第110頁第111頁第112頁第113頁
1999 Microchip Technology Inc.
DS40139E-page 27
PIC12C5XX
6.1
Using Timer0 with an External Clock
When an external clock input is used for Timer0, it
must meet certain requirements. The external clock
requirement is due to internal phase clock (T
OSC
)
synchronization. Also, there is a delay in the actual
incrementing of Timer0 after synchronization.
6.1.1
EXTERNAL CLOCK SYNCHRONIZATION
When no prescaler is used, the external clock input is
the same as the prescaler output. The synchronization
of T0CKI with the internal phase clocks is
accomplished by sampling the prescaler output on the
Q2 and Q4 cycles of the internal phase clocks
(Figure 6-4). Therefore, it is necessary for T0CKI to be
high for at least 2T
OSC
(and a small RC delay of 20 ns)
and low for at least 2T
OSC
(and a small RC delay of
20 ns). Refer to the electrical specification of the
desired device.
When a prescaler is used, the external clock input is
divided by the asynchronous ripple counter-type
prescaler so that the prescaler output is symmetrical.
For the external clock to meet the sampling
requirement, the ripple counter must be taken into
account. Therefore, it is necessary for T0CKI to have a
period of at least 4T
OSC
(and a small RC delay of
40 ns) divided by the prescaler value. The only
requirement on T0CKI high and low time is that they
do not violate the minimum pulse width requirement of
10 ns. Refer to parameters 40, 41 and 42 in the
electrical specification of the desired device.
6.1.2
TIMER0 INCREMENT DELAY
Since the prescaler output is synchronized with the
internal clocks, there is a small delay from the time the
external clock edge occurs to the time the Timer0
module is actually incremented. Figure 6-4 shows the
delay from the external clock edge to the timer
incrementing.
6.1.3
OPTION REGISTER EFFECT ON GP2 TRIS
If the option register is set to read TIMER0 from the pin,
the port is forced to an input regardless of the TRIS reg-
ister setting.
FIGURE 6-4:
TIMER0 TIMING WITH EXTERNAL CLOCK
Increment Timer0 (Q4)
External Clock Input or
Prescaler Output
(2)
Q1
Q2
Q3 Q4
Q1
Q2
Q3 Q4
Q1
Q2
Q3 Q4
Q1
Q2
Q3 Q4
Small pulse
misses sampling
Timer0
T0
T0 + 1
T0 + 2
External Clock/Prescaler
Output After Sampling
(3)
Note 1:
2:
3:
Delay from clock input change to Timer0 increment is 3Tosc to 7Tosc. (Duration of Q = Tosc).
Therefore, the error in measuring the interval between two edges on Timer0 input =
±
4Tosc max.
External clock if no prescaler selected, Prescaler output otherwise.
The arrows indicate the points in time where sampling occurs.
(1)
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| 12C509 | Test Prod Wire; Conductor Size AWG:18; No. Strands x Strand Size:65 x 36; Jacket Color:White; Conductor Material:Copper; Jacket Material:Rubber; Leaded Process Compatible:Yes; Number of Conductors:1 RoHS Compliant: Yes |
| 12C671 | Test Prod Wire; Conductor Size AWG:18; No. Strands x Strand Size:65 x 36; Jacket Color:White; Conductor Material:Copper; Jacket Material:Rubber; Leaded Process Compatible:Yes; Number of Conductors:1 RoHS Compliant: Yes |
| 12C672 | Test Prod Wire; Conductor Size AWG:18; No. Strands x Strand Size:65 x 36; Jacket Color:Black; Conductor Material:Copper; Jacket Material:Rubber; Leaded Process Compatible:Yes; Number of Conductors:1; Outer Diameter:0.144" RoHS Compliant: Yes |
| 12CE673 | HookUp/Lead Wire; Conductor Size AWG:18; No. Strands x Strand Size:65 x 36; Jacket Color:Black; Conductor Material:Copper; Jacket Material:Rubber; Leaded Process Compatible:Yes; Number of Conductors:1; Outer Diameter:0.144" RoHS Compliant: Yes |
| 12CGQ150 | SCHOTTKY RECTIFIER |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| 12C508P | 制造商:Motorola Inc 功能描述: |
| 12C5B | 制造商:AMPERITE CO INC 功能描述:RELAY;TIME DELAY,12VLTG,CLOSED,,MINI |
| 12C5SB | 制造商:Olympic Controls Corporation 功能描述: |
| 12C5T | 制造商:OlympicControls Corp/Amperite Co 功能描述:Electromechanical Relay SPST-NC 3A 12VDC 12VAC Through Hole |
| 12C5XB | 制造商:OlympicControls Corp/Amperite Co 功能描述:Electromechanical Relay SPST-NC 3A 12VDC 12VAC Panel Mount |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。