I am currently unable to desgin a binary to BCD converter using datapath compone

Question

I am currently unable to desgin a binary to BCD converter using datapath components. Here is the description: In order to display the 5-bit binary number in decimal, you will design a Binary to BCD Converter. A BCD number is a number that uses a 4-bit binary number to represent each decimal digit. For example, the binary number 1111 (15 in decimal), can be encoded as BCD number as 0001 0101. As such, the Binary to BCD Converter has a 5-bit input, Cnt, and two 4-bit outputs, Tens and Ones, corresponding to the binary representation of the tens and ones digit of the decimal equivalent. Given that each output is a binary representation of a decimal digit, the range of possible output values should be 0 to 9.

Explanation / Answer

These monolithic converters are derived from the 256-bit read only memories, DM5488, and DM7488. Emitter con- nections are made to provide direct read-out of converted codes at outputs Y8 through Y1, as shown in the function tables. These converters demonstrate the versatility of a read only memory in that an unlimited number of reference tables or conversion tables may be built into a system. Both of these converters comprehend that the least significant bits (LSB) of the binary and BCD codes are logically equal, and in each case the LSB bypasses the converter as illus- trated in the typical applications. This means that a 6-bit converter is produced in each case. Both devices are cas- cadable to N bits. An overriding enable input is provided on each converter which when taken high inhibits the function, causing all out- puts to go high. For this reason, and to minimize power consumption, unused outputs Y7 and Y8 of the 185A and all ``don't care'' conditions of the 184 are programmed high. The outputs are of the open-collector type. DM74184 BCD-TO-BINARY CONVERTERS The 6-bit BCD-to-binary function of the DM74184 is analo- gous to the algorithm: a. Shift BCD number right one bit and examine each dec- ade. Subtract three from each 4-bit decade containing a binary value greater than seven. b. Shift right, examine, and correct after each shift until the least significant decade contains a number smaller than eight and all other converted decades contain zeros. In addition to BCD-to-binary conversion, the DM74184 is programmed to generate BCD 9's complement or BCD 10's complement. Again, in each case, one bit of the comple- ment code is logically equal to one of the BCD bits; there- fore, these complements can be produced on three lines. As outputs Y6, Y7 and Y8 are not required in the BCD-to-bi- nary conversion, they are utilized to provide these comple- ment codes as specified in the function table when the de- vices are connected as shown. DM74185A BINARY-TO-BCD CONVERTERS The function performed by these 6-bit binary-to-BCD con- verters is analogous to the algorithm: a. Examine the three most significant bits. If the sum is greater than four, add three and shift left one bit. b. Examine each BCD decade. If the sum is greater than four, add three and shift left one bit. c. Repeat step b until the least-significant binary bit is in the least-significant BCD location. Absolute Maximum Ratings (Note) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/Distributors for availability and specifications. Supply Voltage 7V Input Voltage 5.5V Output Voltage 7V Operating Free Air Temperature Range 0§C to a70§C Storage Temperature Range b65§C to a150§C

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