Why is a drawing pin called a drawing pin?
Used to hold drawings flat... Because they used to be used in draughting offices to hold plans flat on drawing boards - the wooden boards were resistant to normal pins and the broad top of the drawing pin enabled them to be pushed in without damaging the paper.
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I don't know - try putting it on scales!
Pin Description The following describes the function of each pin: A8 - A15 (Output 3 State) Address Bus ; The most significant 8 bits of the memory address or the 8 bits… of the I/0 address,3 stated during Hold and Halt modes. AD0 - 7 (Input/Output 3state) Multiplexed Address/Data Bus; Lower 8 bits of the memory address (or I/0 address) appear on the bus during the first clock cycle of a machine state. It then becomes the data bus during the second and third clock cycles. 3 stated during Hold and Halt modes. ALE (Output) Address Latch Enable: It occurs during the first clock cycle of a machine state and enables the address to get latched into the on chip latch of peripherals. The falling edge of ALE is set to guarantee setup and hold times for the address information. ALE can also be used to strobe the status information. ALE is never 3stated. S0, S1 (Output) IO/M- (Output) IO/M- indicates whether the Read/Write is to memory or l/O (Tristated during Hold and Halt modes) S0, S1, and IO/M- represent Data Bus Status. Encoded status of the bus cycle: S0 S1 IO/M- 0 0 * Halt State (IO/M- Tristated) 0 1 0 Memory Read 0 1 1 I/O Read 1 0 0 Memory Write 1 0 1 I/O Write 1 1 0 Opcode Fetch 1 1 1 Interrupt Acknowledge S1 can be used as an advanced R/W status. If used this way, it should not be sampled until the trailiing edge of ALE. RD- (Output 3state) READ; indicates the selected memory or I/O device is to be read and that the Data Bus is available for the data transfer. Tristated during Hold and Halt modes. The processor samples the data bus about one half clock cycle before the trailing edge of RD-. WR- (Output 3state) WRITE; indicates the data on the Data Bus is to be written into the selected memory or I/O location. Data is set up at the trailing edge of WR. Tristated during Hold and Halt modes. The data bus is held valid for about one half clock cycle beyond the trailing edge of WR-, or until the leading edge of ALE. It is important to realize that any external bus drivers must not be dropped at the trailing edge of WR- because that creates a race condition - Use ALE to drop the drivers if needed. READY (Input) If Ready is high during a read or write cycle, it indicates that the memory or peripheral is ready to send or receive data. If Ready is low, the CPU will wait for Ready to go high before completing the read or write cycle. It is sampled about one half clock cycle after ALE goes false, on the rising edge of CLK. Note that Ready is sampled about one half clock cycle after the trailing edge of ALE, and this is not a lot of time - make sure your address/ready decoders are fast enough to respond. HOLD (Input) HOLD; indicates that another Master is requesting the use of the Address and Data Buses. The CPU, upon receiving the Hold request. will relinquish the use of buses as soon as the completion of the current machine cycle. Internal processing can continue. The processor can regain the buses only after the Hold is removed. When the Hold is acknowledged, the Address, Data, RD-, WR-, and IO/M- lines are 3stated. HLDA (Output) HOLD ACKNOWLEDGE; indicates that the CPU has received the Hold request and that it will relinquish the buses in the next clock cycle. HLDA goes low after the Hold request is removed. The CPU takes the buses one half clock cycle after HLDA goes low. INTR (Input) INTERRUPT REQUEST; is used as a general purpose interrupt. It is sampled only during the next to the last clock cycle of the instruction. If it is active, the Program Counter (PC) will be inhibited from incrementing and an INTA will be issued. During this cycle a RESTART or CALL instruction can be inserted to jump to the interrupt service routine. The INTR is enabled and disabled by software. It is disabled by Reset and immediately after an interrupt is accepted. INTA (Output) INTERRUPT ACKNOWLEDGE; is used instead of (and has the same timing as) RD during the Instruction cycle after an INTR is accepted. It can be used to activate the 8259 Interrupt chip or some other interrupt port. RESTART INTERRUPTS; These three inputs have the same timing as INTR except they cause an internal RESTART to be automatically inserted. RST 7.5 ~~ Highest Priority (Edge triggered) RST 6.5 ~~ Medium Priority (Level triggered) RST 5.5 ~~ Lowest Priority (Level triggered) The priority of these interrupts is ordered as shown above. These interrupts have a higher priority than the INTR. They can be masked with the SIM instruction. TRAP (Input) (Edge and Level triggered) Trap interrupt is a nonmaskable restart interrupt. It is recognized at the same time as INTR. It is unaffected by any mask or Interrupt Enable. It has the highest priority of any interrupt. RESET IN- (Input) Reset sets the Program Counter to zero and resets the Interrupt Enable and HLDA flipflops. None of the other flags or registers (except the instruction register) are affected The CPU is held in the reset condition as long as Reset is applied. RESET OUT (Output) Indicates CPlJ is being reset. Can be used as a system RESET. The signal is synchronized to the processor clock. X1, X2 (Input) Crystal or R/C network connections to set the internal clock generator X1 can also be an external clock input instead of a crystal. The input frequency is divided by 2 to give the internal operating frequency. CLK (Output) Clock Output for use as a system clock when a crystal or R/ C network is used as an input to the CPU. The period of CLK is twice the X1, X2 input period. SID (Input) Serial input data line The data on this line is loaded into accumulator bit 7 whenever a RIM instruction is executed. SOD (output) Serial output data line. The output SOD is set or reset as specified by the SIM instruction. Vcc +5 volt supply. Vss Ground Reference.
Yes, it is, and the main reason is pressure. It has a small end, so that there is a more concentrated pressure being applied to whatever you push it in to. There is a big …surface area at the end, so that you don't injury your thumb hen pressing down; the pressure is spread out all across it, reducing pain. Because of the large area, you can apply the most pressure you can.
A drawing pin (British English) is known as a thumb tack ora push pin in American English. Other nails for a drawingpin come from the materials that they are made from, su…ch as, brass tack, tin tack, and iron tack.
becoz it can easily pierce through anything...(when it is sharp)
Do you mean a drawing "pen?"
They call it the thumbtack! xx Love Bobthebuilder
a drawing pin have seven eyes. there are 4 located on the cilidrical top and 3 located beneath that.
Not if it is solid brass. Brass is a non-ferrous metal, and therefore, not magnetic.
I think its because the point has a small surface area which makes it easier to press down on. p=F/A pressure=force/area (the area is small, you do not need as much pressure…) hope this helps if u need to double check
To hold things in more
Just use a sieve that the sugar will go through but the pins won't. However I don't think this is the answer Science Quest One is looking for.
In Intel 8085
The pin diagram of AND gate means the pin diagram of IC 7400. New software came handy to draw such complicated diagrams. You can go to the link in the "Sources and related lin…ks" down below and download the smartdraw tool where you can drag and drop such ready made shapes. Corel draw graphic suite is another such tool.
Back in the good old days, all plans for building, machinery anything that was designed, was done so by drawing it on a large flat board using large pieces of paper. These boa…rds were set up on a easel type frame so the draftsman, architect, engineer etc could lay out his design and be drawn to scale. This paper was subject to the forces of gravity and would slide off. One day, someone realised that to keep securing this paper needed a fastener that could be simply attached and extracted. Viola, the drawing pin. In some places, the term thumb tacks became more synonomous with this ingeneous little device, but originally they were drawing pins which differentiated them from other pins thus avoiding someone bringing the wrong pins when asked such as dressmaking pins, hatpins rolling pins etc.
It is made of metal because it has to be able to punch through thecard or paper.
yes or no