Parameterized Macro: Single-bit Synchronizer
- MACRO_GROUP: XPM
- MACRO_SUBGROUP: XPM_CDC
Introduction
This macro synchronizes a one bit signal from the source clock domain to the destination clock domain.
For proper operation, the input data must be sampled two or more times by the destination clock. You can define the number of register stages used in the synchronizers. An optional input register may be used to register the input in the source clock domain prior to it being synchronized. You can also enable a simulation feature to generate messages to report any potential misuse of the macro.
Port Descriptions
| Port | Direction | Width | Domain | Sense | Handling if Unused | Function |
|---|---|---|---|---|---|---|
| dest_clk | Input | 1 | NA | EDGE_RISING | Active | Clock signal for the destination clock domain. |
| dest_out | Output | 1 | dest_clk | NA | Active | src_in synchronized to the destination clock domain. This output is registered. |
| src_clk | Input | 1 | NA | EDGE_RISING | 0 |
Input clock signal for src_in if SRC_INPUT_REG = 1. Unused when SRC_INPUT_REG = 0. |
| src_in | Input | 1 | src_clk | NA | Active | Input signal to be synchronized to dest_clk domain. |
Design Entry Method
| Instantiation | Yes |
| Inference | No |
| IP and IP Integrator Catalog | No |
Available Attributes
| Attribute | Type | Allowed Values | Default | Description |
|---|---|---|---|---|
| DEST_SYNC_FF | DECIMAL | 2 to 10 | 4 | Number of register stages used to synchronize signal in the destination clock domain. |
| INIT_SYNC_FF | DECIMAL | 0, 1 | 0 |
0- Disable behavioral simulation initialization value(s) on synchronization registers. 1- Enable behavioral simulation initialization value(s) on synchronization registers. |
| SIM_ASSERT_CHK | DECIMAL | 0, 1 | 0 |
0- Disable simulation message reporting. Messages related to potential misuse will not be reported. 1- Enable simulation message reporting. Messages related to potential misuse will be reported. |
| SRC_INPUT_REG | DECIMAL | 1, 0 | 1 |
0- Do not register input (src_in) 1- Register input (src_in) once using src_clk |