WB_PWMX - Pin Description
Frozen Content
The following pin description is for the WB_PWMX when used on the schematic. In an OpenBus System, although the same signals are present, the abstract nature of the system hides the pin-level Wishbone interfaces. The Controller's external interface signals will be made available as sheet entries, associated with the parent sheet symbol used to reference the underlying OpenBus System.
Table 1. WB_PWMX pin description.| Name | Type | Polarity / Bus size | Description |
|---|---|---|---|
| Control Signals | |||
| CLK_I | I | Rise | External system clock |
| RST_I | I | High | External system reset |
| Host Processor Interface Signals | |||
| STB_I | I | High | Strobe signal. When asserted, indicates the start of a valid Wishbone data transfer cycle |
| CYC_I | I | High | Cycle signal. When asserted, indicates the start of a valid Wishbone cycle |
| ACK_O | O | High | Standard Wishbone device acknowledgement signal. When this signal goes high, the WB_PWMX Controller (Wishbone Slave) has finished execution of the requested action and the current bus cycle is terminated |
| ADR_I | I | 3 | Standard Wishbone address bus, used to select an internal register of the Wishbone slave device for writing to/reading from. |
| DAT_O | O | 8 | Data to be sent to an external Wishbone master device (e.g. host processor) |
| DAT_I | I | 8 | Data received from an external Wishbone master device (e.g. host processor) |
| WE_I | I | Level | Write enable signal. Used to indicate whether the current local bus cycle is a Read or Write cycle: 0 = Read |
| INT_O | O | High | Interrupt signal. Used to alert the host to the presence of a counter overflow event. This can occur when either the PWM Counter or Pre-scaler Counter counts past zero. Each interrupt source is individually enabled. |
| Outputs | |||
| PWMP | O | High | Differential Pulse-Width-Modulated rectangular wave output signal. PWMP = positive side of signal |
| PWMN | O | Low | |