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8 Bits Wide
just a note: Clarify your question Bit-addressable registers are registers that its bits can be modified individually. that means if you have register named "ACC" that is bit addressable , you can change its bits (D0 -D7) individually by special instructions SETB and CLR. ex: SETB ACC.3 ; will set bit number 4 (remember bit 0) in the register in 8051 there are many bit-addressable registers such as A (ACC), B, SCON, PCON, TCON, p0,p1,p2,p3 . best wishes, drdigital.
how many interrupts in 8051
In the context of the 8051 microcontroller, Tmp 1 and Tmp 2 refer to temporary registers or memory locations used during the execution of instructions. These temporary registers are often utilized by the CPU to hold intermediate data or results during arithmetic and logical operations. They help optimize processing by reducing the need to access slower main memory frequently. However, specific naming conventions like Tmp 1 and Tmp 2 may vary, as the 8051 architecture mainly utilizes general-purpose registers for such temporary storage.
In other words, how do you save temporary data such as data stored in registers r0 to r7 ? The simplest way to use on-chip RAM of the 8051 is to compile your C code with the "--model-small" small memory model option of the SDCC compiler, which tells it to put all variables in on-chip RAM of the 8051.
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Data transfer instructions in the 8051 microcontroller are used to move data between registers, memory, and I/O ports. Key instructions include MOV (to transfer data between registers or memory), MOVC (to move data from code memory), and MOVX (to access external data memory). These instructions facilitate the manipulation and transportation of data within the microcontroller's architecture, enabling various operations in embedded applications.
The bit addressable memory in 8051 is compose from 210 bits: - bit address space: 20H - 2FH bytes RAM = 00H - 7FH bits address; - SFR registers; The following addresses are NOT bit addressable, only 1-byte addressable: - 32 bytes RAM from 00H to 1FH (R0 - R7 registers in all four banks); - 80 bytes RAM general user from 30H to 7FH.
registers are five types.
The microcontrollers have an 8-bit data bus. They are capable of addressing 64K of program memory and a separate 64K of data memory. The 8051 has 4K of code memory implemented as on-chip Read Only Memory (ROM). The 8051 has 128 bytes of internal Random Access Memory (RAM). The 8051 has two timer/counters, a serial port, 4 general purpose parallel input/output ports, and interrupt control logic with five sources of interrupts. Besides internal RAM, the 8051 has various Special Function Registers (SFR), which are the control and data registers for on-chip facilities. The SFRs also include the accumulator, the B register, and the Program Status Word (PSW), which contains the CPU flags. << SHARMILA TANDEL (B.E) ELECTRONICS >>
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The 8051 microcontroller includes a set of arithmetic and logical instructions that facilitate basic mathematical operations and data manipulation. Arithmetic instructions include addition, subtraction, multiplication, and division, allowing operations on registers and memory. Logical instructions perform operations like AND, OR, XOR, and NOT, enabling bitwise manipulation of data. Additionally, bit manipulation instructions allow for setting, clearing, and toggling specific bits within registers, enhancing control over individual data bits.