Assignment 1. Write a simple character based encryption engine. (50 pts) The encryption algorithm consists of two LFSR registers, one 17 bits long and one 23 bits long. The lower 8 bits of each LFSR are XOR'd together and that result is XOR'd with the plaintext data characters. The input plaintext data characters are c asserted. The encrypted ciphertext data characters are clocked out of the encryption engine whenever the VALID output is asserted. A top-level block diagram of the encryption engine is shown in the diagranm below the encryption engine whenever the READY input is 40-BIT KEY 39:23 22:0 17-BIT LFSR 23-BIT LFSR PLAINTEXT 9(+- CIPHERTEXT The two LFSRs are initialized using a 40-bit key that is made up of five 8-bit ASClIl characters. This five character key data is loaded into the 2 LFSRs whenever the LOAD input is asserted. As each character is encrypted, the two LFSRs are shifted 8 times to create 8 fresh bits for each LFSR stream. The two LFSRs have the following structure: Shift Direction 23 22 21 20 19 18 17 3 2 1 Shift Direction 116|15|14|13 | 13|2| 1 Note that bits 8:1 of each LFSR are the bits that are used for the data encryption. Assignment 1. Write a simple character based encryption engine. (50 pts) The encryption algorithm consists of two LFSR registers, one 17 bits long and one 23 bits long. The lower 8 bits of each LFSR are XOR'd together and that result is XOR'd with the plaintext data characters. The input plaintext data characters are c asserted. The encrypted ciphertext data characters are clocked out of the encryption engine whenever the VALID output is asserted. A top-level block diagram of the encryption engine is shown in the diagranm below the encryption engine whenever the READY input is 40-BIT KEY 39:23 22:0 17-BIT LFSR 23-BIT LFSR PLAINTEXT 9(+- CIPHERTEXT The two LFSRs are initialized using a 40-bit key that is made up of five 8-bit ASClIl characters. This five character key data is loaded into the 2 LFSRs whenever the LOAD input is asserted. As each character is encrypted, the two LFSRs are shifted 8 times to create 8 fresh bits for each LFSR stream. The two LFSRs have the following structure: Shift Direction 23 22 21 20 19 18 17 3 2 1 Shift Direction 116|15|14|13 | 13|2| 1 Note that bits 8:1 of each LFSR are the bits that are used for the data encryption