olo_intf_uart¶
Status Information¶
VHDL Source: olo_intf_uart
Description¶
Overview¶
This entity implements an UART. It is designed to run high baud-rates (up to 10% of the clock frequency).
Parity checking for RX and parity calculation for TX is done internally in olo_intf_uart.
The Uart_Rx line is synchronized internally inside olo_intf_uart.
The UART protocol is commonly known and hence not described here. A good and concise description of the protocol can be found here.
Generics¶
| Name | Type | Default | Description |
|---|---|---|---|
| ClkFreq_g | real | - | Clock Frequency in Hz |
| BaudRate_g | real | 115.2e3 | Baud rate |
| DataBits_g | positive | 8 | Number of data bits Range: 7 ... 9 |
| StopBits_g | string | "1" | Number of stop bits. Allowed values: "1", "1.5", "2" |
| Parity_g | string | "none" | Parity setting: "none" : No parity bit "even" : parity bit = 0 when there is an even number of ones in data "odd" : parity but = 0 when there is an odd number of ones in data |
Interfaces¶
Control¶
| Name | In/Out | Length | Default | Description |
|---|---|---|---|---|
| Clk | in | 1 | - | Clock - Frequency must e at least 10x higher than BaudRate_g |
| Rst | in | 1 | - | Reset input (high-active, synchronous to Clk) |
RX Data Interface¶
Interface for data received over UART. There is no Ready signal - hence the consumer must be able to accept data immediately.
| Name | In/Out | Length | Default | Description |
|---|---|---|---|---|
| Rx_Valid | out | 1 | N/A | AXI-S handshaking signal for Rx_Data |
| Rx_Data | out | DataBits_g | N/A | Data received over UART |
| Rx_ParityError | out | 1 | N/A | Asserted if the parity bit does not match the expected value according to the data received (hence there was a bit error). |
TX Data Interface¶
Interface for data to be sent over UART.
| Name | In/Out | Length | Default | Description |
|---|---|---|---|---|
| Tx_Valid | in | 1 | '0' | AXI-S handshaking signal for Tx_Data |
| Tx_Ready | out | 1 | N/A | AXI-S handshaking signal for Tx_Data |
| Tx_Data | in | DataBits_g | 0 | Data to be sent over UART |
UART Interface¶
| Name | In/Out | Length | Default | Description |
|---|---|---|---|---|
| Uart_Tx | out | 1 | N/A | UART transmit signal |
| Uart_Rx | in | 1 | '1' | UART receive signal |
Detailed Description¶
No detailed description is given. The UART is very simple.