szadeklord
Newbie level 2
So I have tried tackling this problem, but I cant seem to get anywhere. I dont know if I am making things too complex. I came up with this state diagram and state table. But I dont know if this is too complex. I dont even know how to implement it from my state table. I described my issue below.
Okay I have a system which consists of a spinning circular disk and stationary probes A (at 12 o’clock on the disk frame) and B (at 3 o’clock on the disk frame). One half of the disk is black and causes a either probe to read 1 when the black portion of the disk passes underneath it. The other half of the disk is white and causes a probe to register 0. The system has three synchronous inputs (A, B and ENABLE) and the two moore outputs (VALID and DIRECTION). I need to figure out if the disc is spinning clockwise or counterclockwise.
- When the disk is spinning at full speed ENABLE is asserted (1). While enabled, the clock frequency will be high enough to guarantee that the disk is sampled 8 times per rotation. Otherwise (when the disk is stopped or changing direction), the external system holds ENABLE low (0).
- The value of the DIRECTION should be low (0) if the direction of the spin is counterclockwise. The value of DIRECTION should be high (1) if the direction of spin is clockwise. The value of DIRECTION output is ignored (and thus can be treated as don’t care) until valid is asserted.
- Whenever ENABLE is low or when ENABLE is high and the DIRECTION is not yet valid, the output VALID is held low (0). Once the direction of the spin is determined (and the value of direction set accordingly) VALID should be asserted.
- Once the VALID is asserted, the outputs should be held stable until ENABLE goes low.
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Am I able to do this with less states? Is it possible to solve this problem with only 8 states? (3 flip flops)
Okay I have a system which consists of a spinning circular disk and stationary probes A (at 12 o’clock on the disk frame) and B (at 3 o’clock on the disk frame). One half of the disk is black and causes a either probe to read 1 when the black portion of the disk passes underneath it. The other half of the disk is white and causes a probe to register 0. The system has three synchronous inputs (A, B and ENABLE) and the two moore outputs (VALID and DIRECTION). I need to figure out if the disc is spinning clockwise or counterclockwise.
- When the disk is spinning at full speed ENABLE is asserted (1). While enabled, the clock frequency will be high enough to guarantee that the disk is sampled 8 times per rotation. Otherwise (when the disk is stopped or changing direction), the external system holds ENABLE low (0).
- The value of the DIRECTION should be low (0) if the direction of the spin is counterclockwise. The value of DIRECTION should be high (1) if the direction of spin is clockwise. The value of DIRECTION output is ignored (and thus can be treated as don’t care) until valid is asserted.
- Whenever ENABLE is low or when ENABLE is high and the DIRECTION is not yet valid, the output VALID is held low (0). Once the direction of the spin is determined (and the value of direction set accordingly) VALID should be asserted.
- Once the VALID is asserted, the outputs should be held stable until ENABLE goes low.
- - - Updated - - -
Am I able to do this with less states? Is it possible to solve this problem with only 8 states? (3 flip flops)