The following problems are about bit masks. 1. Masks and Shifts. 1.1 Write one C instruction...

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The following problems are about bit masks. 1. Masks and Shifts. 1.1 Write one C instruction to write bits 5-11 of int a (a has bits 0 to 31) into bits 9 - 15 of int b, without changing any other bits of b. 1.2 Write one C instruction to set int a to 12 if bits 3-7 of int bare 1 and bits 8-12 of b are 0. 2. Write a program which uses bit masking to create a 32-bit integer, n, from 8 hex characters. Your program should input eight ASCII characters that are valid hexadecimal symbols ('0', '1','9'. 'A'..., 'F') into a character array, and then use each of those characters to create a 32-bit number, n. The first character entered should be the least significant nibble, and the last character entered should be the most significant nibble. For example, if the input is these eight characters: 1234ABCD, the resulting value of n should be 0xDCBA4321. Your program should then print out n as a hex number. (Your program does NOT have to insure the inputs are valid hex characters nor that the correct number of characters have been entered.) // the last line must be: printf ("n=0xx\n", n); int main (void) { int i; char c[80]; int n=0; printf("Input> "); fgets (c, sizeof (c), stdin); The following problems are about bit masks. 1. Masks and Shifts. 1.1 Write one C instruction to write bits 5-11 of int a (a has bits 0 to 31) into bits 9-15 of int b, without changing any other bits of b. 1.2 Write one C instruction to set int a to 12 if bits 3-7 of int bare 1 and bits 8-12 of b are 0. 2. Write a program which uses bit masking to create a 32-bit integer, n, from 8 hex characters. Your program should input eight ASCII characters that are valid hexadecimal symbols ('0', '1','9'. 'A'..., 'F') into a character array, and then use each of those characters to create a 32-bit number, n. The first character entered should be the least significant nibble, and the last character entered should be the most significant nibble. For example, if the input is these eight characters: 1234ABCD, the resulting value of n should be 0xDCBA4321. Your program should then print out n as a hex number. (Your program does NOT have to insure the inputs are valid hex characters nor that the correct number of characters have been entered.) // the last line must be: printf ("n=0xx\n", n); int main (void) ( int i; char c[80]; int n=0; printf("Input> "); fgets (c, sizeof (c), stdin); The following problems are about bit masks. 1. Masks and Shifts. 1.1 Write one C instruction to write bits 5-11 of int a (a has bits 0 to 31) into bits 9 - 15 of int b, without changing any other bits of b. 1.2 Write one C instruction to set int a to 12 if bits 3-7 of int bare 1 and bits 8-12 of b are 0. 2. Write a program which uses bit masking to create a 32-bit integer, n, from 8 hex characters. Your program should input eight ASCII characters that are valid hexadecimal symbols ('0', '1','9'. 'A'..., 'F') into a character array, and then use each of those characters to create a 32-bit number, n. The first character entered should be the least significant nibble, and the last character entered should be the most significant nibble. For example, if the input is these eight characters: 1234ABCD, the resulting value of n should be 0xDCBA4321. Your program should then print out n as a hex number. (Your program does NOT have to insure the inputs are valid hex characters nor that the correct number of characters have been entered.) // the last line must be: printf ("n=0xx\n", n); int main (void) { int i; char c[80]; int n=0; printf("Input> "); fgets (c, sizeof (c), stdin); The following problems are about bit masks. 1. Masks and Shifts. 1.1 Write one C instruction to write bits 5-11 of int a (a has bits 0 to 31) into bits 9-15 of int b, without changing any other bits of b. 1.2 Write one C instruction to set int a to 12 if bits 3-7 of int bare 1 and bits 8-12 of b are 0. 2. Write a program which uses bit masking to create a 32-bit integer, n, from 8 hex characters. Your program should input eight ASCII characters that are valid hexadecimal symbols ('0', '1','9'. 'A'..., 'F') into a character array, and then use each of those characters to create a 32-bit number, n. The first character entered should be the least significant nibble, and the last character entered should be the most significant nibble. For example, if the input is these eight characters: 1234ABCD, the resulting value of n should be 0xDCBA4321. Your program should then print out n as a hex number. (Your program does NOT have to insure the inputs are valid hex characters nor that the correct number of characters have been entered.) // the last line must be: printf ("n=0xx\n", n); int main (void) ( int i; char c[80]; int n=0; printf("Input> "); fgets (c, sizeof (c), stdin);

Answer rating: 100% (QA)

Explanation 11 To write bits 511 of a into bits 915 of b without changing any other bits of b we can use bitwise operations like this b b 0x7F 9 a 0x7F 9 Heres how it works step by step 0x7F is a bina... View the full answer