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sequential (57) I2C and SPI protocol

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  https://wodewangzhishime.blogspot.com/2022/06/httpswodewangzhishime_10.html?m=1 . Ref: https://kamchihau.blogspot.com/2022/09/different-frequency.html .  . . John: There're many type of protocol of communication . You might have a look .  https://instrumentationblog.com/communication-protocols/ . // . For example, RJ45, I2C, USB, SPI, RS232, so on and on.  Me: Ok. John: We use the protocol of SPI as an example.  Look at the picture above.  The slave of SPI use the clock line of the master. Me: OK. John: Normally, the master of SPI choose the clock line of the system.  However, hacker hack it. It Become, . Subject [Master of SPI] Interrupt [The clock line of RJ45] <---- Originally it is The clock line of the System.  Object [] Value [pending] . John: If there's carrier wave on the clock line of RJ45 of the master, those carrier wave enter the Slave cause the slave use the clock line of RJ45 too.

sequential (55) Left right shift line

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https://wodewangzhishime.blogspot.com/2022/06/httpswodewangzhishime.html . Ref: https://kamchihau.blogspot.com/2022/10/httpskamchihau_16.html . . . John: See the picture above. Not all the chips have the Left/Right shift line. Left/Right shift line is a field. . For (int i = 0; i<100; i++) { Sum = Sum + i (Right shift) Receiving.  } . __ . For (int i = 100; i>0; i--) { Decrease = decrease - i (Left shift) Sending.  } Subject [I2C] Object [Sum] Interrupt_status [ ] Load_Shift_status [Shift] Left_Right_Shift [ right ] <-- Right shift mean receiving. In the port of SPI, you're not supposed to set it. . Me: The port of I2C is only one line. This one line is used for both receiving and sending. Therefore,  Left/Right Shift line is needed in this case. . John : Other chips doesn't have Left/Right Shift line. . Me: Right shift mean receiving in the port of I2C.  Left shift mean sending in the port of I2C. . John : Spi port has 2 line. One is for receiving.  On...

learning and teaching (36) China teacher and students

https://wodewangzhishime.blogspot.com/2022/05/httpswodewangzhishime_13.html . Ref: https://wodewangzhishime.blogspot.com/2021/10/httpswodewangzhishime_61.html . John: Repeating Kelvin's words is illegal.  You gotta genuinely report the news. Me: Ok. John: 2014, Kelvin use the poison to kill my father in the hospital. Guess what happen ? . . __ . Kelvin : I used the poison to kill John's father. You repeat my words. . Mary (the public relation of the hospital): How do I repeat your words? . Kelvin: You give a phone-call to John. You pretend to feel pity and pretend to sob and say to John, " Your father is miserable. ". . ____________________ . Note:  . 1) She didn't genuinely report the news of that "Me (Mary) is Kelvin's students.". . 2) Instead,  she repeated Kelvin's words by pretending to sob and feel pity and say to John, "John's father is miserable. ". Bradley: Kill those students, e.g., Mary. . Kelvin : Hey ! It's me who...

learning and teaching (7) 3rd Rais killings

https://wodewangzhishime.blogspot.com/2022/05/httpswodewangzhishime_18.html?m=1 . Ref:  https://wodewangzhishime.blogspot.com/2021/09/httpswodewangzhishime_29.html . John : Miuson is the person in this link. https://john-kam.blogspot.com/2026/08/httpsjohnkamchihau_0393008756.html?m=1 . Me: Ok. ___ Kelvin : John is an example.  He's " surveillanced " by the satellite.  It's educational.  Look at this camera.  It hack the satellite of America.  Through the camera,  do you see John is riding bicycles?   Mr. Lee (a legislative personnels of Hong Kong): Yes, but, it's nothing special.  Kelvin : Nothing special ? You mother fucker.  I surveillance John for your own sake not for the God's sake. I ask you to be alert of the details.  You doze off. John didn't wear the helmet while riding the bicycles.  Tomorrow,  you bring this video to see your colleagues and say to them,  "we must legislate that people riding bicycl...

sequential (29) no realistic serial circuit - FM modulation (1)

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https://wodewangzhishime.blogspot.com/2022/04/httpswodewangzhishime_23.html . Ref:  https://chihaukam.blogspot.com/2024/09/blog-post_2.html?m=1 .. . . . . . John: The 2 pictures above are FM modulation. Which one is correct. Me: Logically, the 2nd picture is correct. John (shaking head): No,. The 2nd picture is incorrect. Me: The 1st picture is correct. John: Yes,. . In the 1st picture, there're 2 circuit. They're circuit A and circuit B. In circuit A, the left-side branch is high frequency, 100 Mhz. However, the right-side  branch is low frequency, 80 Mhz. . John: As a result, a electrical current of low frequency which is just 80 Mhz is induced in Circuit B.

sequential (63) - System bus

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https://wodewangzhishime.blogspot.com/2022/03/httpswodewangzhishime_73.html . Ref:   https://kamchihau.blogspot.com/2022/11/httpskamchihau.html . . . John : This article is about System bus.   https://wodewangzhishime.blogspot.com/2023/12/sequential-90-enabling-line.html?m=1  . You may have a look at it first.  Me: Ok. . See the picture above.  . 1) It is a register of serial input.  2) The field of  value of it has 4 bits. 3) The bit of the left-most is the bit of being input. 4)  This register right shift.  . Me: Ok.  . John: There're 3 type of data bus of a serial input in term of their width.  . 1) Bus width 4 bits. 2) Bus width 8 bits. 3) Bus width 32 bits. . John : In the picture,  its Bus width us 4 bits. That mean, during 1 up-cycle of the clock line,  maximum 4 bits are allowed to be input together in the field of value of a register of serial input.  This 4 bits are  ((( 1 . 0 . 1. 0 ))) respe...

sequential (32) Interrupting

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https://wodewangzhishime.blogspot.com/2022/03/httpswodewangzhishime_21.html . Ref:   https://wodewangzhishime.blogspot.com/2022/07/httpswodewangzhishime.html . . . John: In the picture above, R0(0), R0(2), R0(4) are on the parallel input clock line. <--- Note: We can call it as a "process" clock line. Me: However, R0(1), R0(3) are on the serial input clock line. John: Yes,. Me: In code, how do we interpret it? . for (int i=0; i<10; i++) // R0(0) output bits by bits. { R0(3) [i] = i; // R0(3) input bit by bit. } . John: When R0(1) and R0(3) are on the serial input clock line, we call that real interrupt. Me: That mean, when the register isn't on the process clock line, it is on the serial input clock line. John: To some extent, "Yes". Taje a look.  https://wodewangzhishime.blogspot.com/2023/12/sequential-99.html . It  mention about how the  fields work. Or, we can intepret it in this way. . Subject [R0(1)] Interrupt status [ serial input clock line ] Objec...

sequential (27) Code being changed

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  https://wodewangzhishime.blogspot.com/2022/03/httpswodewangzhishime_20.html . Ref:  https://wodewangzhishime.blogspot.com/2022/02/httpswodewangzhishime_3.html?m=1 . . John: Take a look.   https://chihaukam.blogspot.com/2026/01/john-have-look_8.html?m=1 . It say, "Left shifting and stack overflow isn't the principle of hacking. ". See the picture above.  R0 and R1 are 2 independent registers. They have 4 bits. . Me: If they have 4 bits only, there's a problem.  If I wanna do that,  For (int I = 0; I < 8; I ++){} . Me: How can I do that? John : When you press a button,  your code change into . For (int I = 0; I < 4; I ++){} <--- R0 For (int I = 0; I < 4; I ++){} <--- R1 . Me: Who does change it? . John : The system change it.

learning and teaching (39) SARS

https://wodewangzhishime.blogspot.com/2022/03/httpswodewangzhishime_15.html . Ref: https://wodewangzhishime.blogspot.com/2021/12/battlefield-backlines-discriminating.html . . John : Miuson is the person in this link.  https://johnchihau.blogspot.com/2026/05/blog-post_14.html?m=1  . Miss Wang is the person in this link.   https://wodewangzhishime.blogspot.com/2021/10/disavowal.html?m=1 . Me: Ok. ___ . Mr. Lok (a spy from Hong Kong): Why does nobody witness that Miss Wang put the poison (Ebola ) in the dog's food ? . Kelvin : I use the satellite to surveillance the environment of the bakery shop.  I protect Miss Wang.  . Mr. Lok: You are genius.  . Kelvin : You drive a car to the house of John.  You park the car by the gate and Honk. It's the achievement of your professor.   You applaud. . Mr. Lok: I've got it.  __ . Bradley : Kill those students,  e.g., Mr. Lok.  "You" teach him how to hack the satellite.  . Kelvin :...

sequential (41) Architecture of in-out

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  https://wodewangzhishime.blogspot.com/2022/03/httpswodewangzhishime_13.html?m=1 . Ref:   https://wodewangzhishime.blogspot.com/2022/01/httpswodewangzhishime_20.h . . John : The architect of the above circuit is that indeed,  there is no serial input line.  . Me: Ok. . John: Here's a register called "R0" the value of which has 4 bits.  They are b1, b2, b3, b4. . Me: Ok. . John: The power source of the modulator is from RJ45.  RJ45 is at the Up Cycle.  The modulator will output.  A signal is sent to "R0" through a data bus.  . Note: In the architect of Microsoft,  we call that a data bus instead of a parallel input output line. . Me: Is "R0" parallel input or serial input ? . John : In fact,  you can't find a serial input line or a parallel input line in this architect. What's you can find is a line called "Input line". . Me: Then,  how do I know that it's a serial input or parallel input ? . John : If there's a delayed ci...

sequential (38) Interrupting

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https://wodewangzhishime.blogspot.com/2022/03/httpswodewangzhishime_7.html . Ref:  https://kamchihau.blogspot.com/2022/11/blog-post_9.html . . John: Take a look.   https://wodewangzhishime.blogspot.com/2022/03/httpswodewangzhishime_73.html  . It talk about real interrupt. Me: OK. John: Now, we look at the picture above. R0(1) and R0(3) aren't on System clock line. Nor is it on the serial input clock line. What do we call it? Me: We call it "mask" interrupt. John: In code, how do we interpret a mask interrupt? Me: Like this. . if (int i != 0)  { R0(1) is at the stage of "Mask Interrupt". That mean, R0(1) isn't on the serial input clock line. Nor is it on the System clock line. } . John: Take a look.  https://wodewangzhishime.blogspot.com/2023/12/sequential-99.html . It mention about how the fields work in "RAM". Or, we can intepret it in this way. . Subject [R0(1)] Interrupt status [Mask-interrupt] Object [R0(21)] Role [ Master ] value [0]

sequential (66) RJ45 (Protocol) direction of current flow

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    https://wodewangzhishime.blogspot.com/2022/03/httpswodewangzhishime_1.html?m=1 . Ref: https://kamchihau.blogspot.com/2022/10/httpskamchihau_17.html?m=1 . . . . . John : Take a look. https://chihaukam.blogspot.com/2023/10/me-indeed-is-there-any-indias-spy-in.html?m=1 . It mention about a double in/out operational amplifier.  . Me: Ok. . John : See the 2nd  Picture above.  We use Rd+ and TX+ to create a Clk line.  . Me: This clock line is an Alternate current.  . John : Yes, now, b1 send a signal to the input (-) of the operational amplifier.  . Me: How many voltage is this signal ? . John : 4.5 V. . Me: Ok. . John : In fact, only Tx- is induced 4.5 V. Tx+ is  only induced 0.5 V. Why ? Because,  the current direction of Tx+ isn't clear yet. . Me: Common mode block the direction of the current flow of (Tx +). . John : Yes, however,  during the next round, the direction of current flow will be changed.   . Me: Yes, by the...

sequential (43) No realistic serial circuit (data input)

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https://wodewangzhishime.blogspot.com/2022/02/httpswodewangzhishime_26.html . Ref: https://chihaukam.blogspot.com/2024/10/blog-post_52.html?m=1 . . . . John: Now, see the 1st picture above. Which part is correct? Me: Normally, the part of left hand side is correct. That mean, when the data input line is on Up cyle, Gate A and Gate B are on Up cycle. John: You're wrong. The part of right hand side is correct too. Me: That mean, when the data input line is on Up cycle, Gate A can be on Up cycle and Gate B can be on down cycle. John: You're correct. OK. I intepret it in code. If (Gate A = Up cyle) { Set = 1; if (Gate B = Down cyle) { Inverter = true; if (inverter = true) { Gate B = 1; if (Gate B = 1) { Reset = 1; If (Set = 1 & Reset = 1) { The circuit of the Flip Flop = Unstable. } } } } } . John: Now, See 2nd picture above. Which part is correct? Me: Normally, the part of left hand side is correct. That mean, when the clock line is on Up cycle, Gate A and Gate B are on Up cyc...

sequential (48) chosen clock line

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  https://wodewangzhishime.blogspot.com/2022/02/httpswodewangzhishime_25.html . Ref:  https://wodewangzhishime.blogspot.com/2022/02/httpswodewangzhishime_80.html  . . . Me: Indeed, we can use it in this way. . if (commutator_a = true) // Control line create a signal of 1,1,1 { Network serial communication = true; } else if (commutator_b = true) // Control line create a signal of 0,1,1 { Internal serial communication = true; // I give you an example of internal serial communication . for (int i =0; i<10; i++) { Array k[i] = i; } } else if (commutator_c = true) // Control line create a signal of 0,0,0 { Internal parallel communication = true; Parallel input syndronize chosen clock line  } ==

sequential (39) Tri State buffer

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https://wodewangzhishime.blogspot.com/2022/02/httpswodewangzhishime_80.html?m=1 . Ref:  https://wodewangzhishime.blogspot.com/2022/03/httpswodewangzhishime_13.html . . . John : See the Picture above.  Each output bit has a tristate buffer.  In another words,  the parallel output must be enabled.  I give you an example.  . Int register_a = 1010 Int register_b = register_a. . John : In this case, the parallel output of register_a is enabled. . Me: Ok. . John: The parallel output of register_b is disable cause register_b is being set by the others only. register_b is not gonna set the others. Me: It's the concept of "fields of datas". John : In code, we represent them by this way. . Subject [Ststem] Object [register_a] Output available [true]  . Subject [System] Object [register_b] Output available [false]  . John : The system disable the output from register_b.

sequential (47) chosen clock line

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https://wodewangzhishime.blogspot.com/2022/02/httpswodewangzhishime_62.html . Ref: https://wodewangzhishime.blogspot.com/2022/06/what-does-he-need.html . . . Me: R0(1),R0(2),R0(3),R0(4) form a register called register_a. . If (Control = 1,1,1) { Commutator_a = chosen. } else if (Control = 0,1,1) { Commutator_b = chosen. } else if (Contol = 0, 0,0) { commutator_c = chosen; } else if (Control = 0,0,1) { No commutator is chosen; // the status is mask - interrupt. }

sequential (52) Architecture

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https://wodewangzhishime.blogspot.com/2022/02/httpswodewangzhishime_14.html . Ref:  https://kamchihau.blogspot.com/2022/11/impact.html . . . John: The picture above is the normal architecture of control.  There're 3 bits. They are b1, b2 and b3 . 1) The Output of Bit 1 control the load shift line.  2) The Output of Bit 2 control the Output Availability line.  3) The Output of Bit 3 control the Falling Edge trigger line.  . Me: If I wanna change the value of them,  how? . Me: The modulator of RJ45 will send a signal to them during an up cycle.  For example,  the modulator send a signal of (1.1.0) them. As a result,  the Output of Bit 1 will be 1, the Output of Bit 2 will be 1 and the Output of Bit will be 0. . John : In another words,  the load shift line will be 1, the Output Availability line will be 1 and the falling edge trigger line will be 0.

learning and teaching (15) Aden Gulf disaster

https://wodewangzhishime.blogspot.com/2022/02/httpswodewangzhishime_12.html . Ref:  https://wodewangzhishime.blogspot.com/2021/08/plug-off-cable.html . John: Repeating Kelvin's words is illegal.  You gotta genuinely report a news. Me: Ok.  John : Miuson is the person in this link. https://chihaukam.blogspot.com/2025/10/john-take-look.html?m=1 . Me: Ok. John : See. https://wodewangzhishime.blogspot.com/2022/06/httpswodewangzhishime.html?m=1 The matter isn't over yet. ____________ . Kelvin : See.  I click a button.  I can access the database of the hospital.   No record of my accessing the database is left.  Nobody can trace me.  Isn't it high tech ? You repeat my words.  . Mary: How do I repeat your words ? . Kelvin : You give a phone-call to John.  You ask John, "You provide evidence. ". . ____ . Note : She didn't genuinely report the news of that me (Mary) is Kelvin's students.  She only repeat the words of Kelvin.  . Br...