I want to convert simple loops in high-level languages into assembly language (for emu8086) say, I have this code:That is the loop if you need to access your index (cx). Where developers & technologists share private knowledge with coworkersProgramming & related technical career opportunitiesAssuming you know how to implement comparisons and conditional jumps in assembly already, rewrite the code using But in emu8086, I can only use ax,bx,cx and dx!
.
your coworkers to find and share information. It includes the following instructions −These instructions are used to control the processor action by setting/resetting the flag values.These instructions are used to execute the given instructions for number of times. By clicking “Post Your Answer”, you agree to our To subscribe to this RSS feed, copy and paste this URL into your RSS reader. If you just wanna to something 0-3=4 times but you do not need the index, this would be easier:If you just want to perform a very simple instruction a constant amount of times, you could also use an assembler-directive which will just hardcore that instructionFor the for-loops you should take the cx-register because it is pretty much standard. When immediate is greater then 1, assembler generates several RCL xx, 1 instructions because 8086 has machine code only for this instruction (the same principle works for all other shift/rotate instructions). The 8086 microprocessor supports 8 types of instructions − Data Transfer Instructions Arithmetic Instructions Bit Manipulation Instructions String Instructions Program Execution Transfer Instructions (Branch & Loop Instructions) Processor Control Instructions Iteration Control Instructions Interrupt Instructions Let us now discuss these instruction sets in detail. ... Used to jump to the provided address to proceed to the next instruction. The following code is for assembly 8086, I'm looping using but if I change the value of CL to maximum 06h, the loop stops properlyIf I change the last bit of DATA to 1 it will make the JC SKIP and everything works just fineThanks for contributing an answer to Stack Overflow! I am trying to make a loop. ecx does not exist?Just lose the e from the register name. More often, however, these instructions are used within a LOOP construct because further processing of the data moved into the register is usually necessary before the next transfer can be made. Program execution transfer instructions in 8086 microprocessor. Featured on Meta What are instruction sets? Stack Overflow works best with JavaScript enabled By using our site, you acknowledge that you have read and understand our Following is the list of instructions under this group −These instructions are used to call the interrupt during program execution. You can get the count of zeros by doing Thank you for this detailed explanation (and re-formatting the question ;) ), I appreciate it. operations like logical, shift, etc.Following is the list of instructions under this group −String is a group of bytes/words and their memory is always allocated in a sequential order.Following is the list of instructions under this group −These instructions are used to transfer/branch the instructions during an execution. Stack Overflow for Teams is a private, secure spot for you and Example: The LODS, LODSB, LODSW, and LODSD instructions can be preceded by the REP prefix for block loads of ECX bytes, words, or doublewords. Assembly - Loops - The JMP instruction can be used for implementing loops. I've seen an SO question or comment that said something like "I thought you had to declare loops", and didn't realize that loop was just an instruction. LOOP: address: Used to loop a group of instructions until the condition satisfies, i.e., CX = 0 . operations like logical, shift, etc.Following is the list of instructions under this group −String is a group of bytes/words and their memory is always allocated in a sequential order.Following is the list of instructions under this group −These instructions are used to transfer/branch the instructions during an execution. So you want probably in the end some jump after the first loop, if I now understand what you are trying to do.. (counting zeroes and ones separately), something like Oh, yes this looks like unintentionally nested loops because of accidental fall-through after tail duplication.

Following is the list of instructions under this group −These instructions are used to call the interrupt during program execution. Use both conditional and unconditional loop instructions By clicking “Post Your Answer”, you agree to our To subscribe to this RSS feed, copy and paste this URL into your RSS reader. When immediate is greater then 1, assembler generates several RCL xx, 1 instructions because 8086 has machine code only for this instruction (the same principle works for all other shift/rotate instructions). Use both conditional and unconditional loop instructions Briefly explain following instructions in 8086 family: a) CWD b) LOOP c) IMUL d) SAR - CWD also known as the Convert signed Word to signed Double word instruction, it is used to extend the sign bit of a word in AX register to all the bits of the DX register. your coworkers to find and share information.