Counter (8-bit)
Use DigiSim's fixed 8-bit up-counter for modulo-256 counting. It increments on rising CLK when EN=1, clears asynchronously when CLR=1, and treats LD as reserved.
Overview
The DigiSim 8-bit Counter is a fixed unsigned up-counter from 0x00 through 0xFF.
Exact DigiSim.io Implementation
| Pin | Role |
|---|---|
| CLK | Rising-edge clock. |
| CLR | Active-HIGH asynchronous clear. |
| EN | Active-HIGH count enable. |
| LD | Reserved; currently has no effect. |
| Q0–Q7 | Current count; Q0 is LSB. |
| CY | HIGH while the current count is 0xFF. |
Usage Notes
- CLR has priority and acts without a clock edge.
- There are no parallel data inputs, so LD cannot load a value.
- The component does not count down and has no OE pin; all outputs are always driven.
Learning Path
Prerequisites
Next Steps
Frequently Asked Questions
What is the range of an 8-bit counter?
The count spans 0x00–0xFF and wraps to 0x00 after 255. Q0–Q7 are always driven, CY is HIGH while the current count equals 0xFF, and the component has no down-count or OE input.
Can the 8-bit Counter load an arbitrary value?
No. The exposed LD pin is reserved and currently has no effect. Use a Register and external increment/select logic if you need parallel loading or a custom count sequence.