This a circuit for universal transmitter and receiver circuit. This circuit is based on PC16550D IC from National Semiconductor. This circuit have basic circuit that can be control using microcontroler. This is the figure of the circuit;
The PC16550D is an improved version of the original 16450 Universal Asynchronous Receiver/Transmitter (UART). Functionally identical to the 16450 on powerup (CHARACTER mode)* the PC16550D can be put into an alternate mode (FIFO mode) to relieve the CPU of excessive software overhead. In this mode internal FIFOs are activated allowing 16 bytes (plus 3 bits of error data per byte in the RCVR FIFO) to be stored in both receive and transmit modes. All the logic is on chip to minimize system overhead and maximize system efficiency. Two pin functions have been changed to allow signaling of DMA transfers.
The UART performs serial-to-parallel conversion on data characters received from a peripheral device or a MODEM, and parallel-to-serial conversion on data characters received from the CPU. The CPU can read the complete status of the UART at any time during the functional operation. Status information reported includes the type and condition of the transfer operations being performed by the UART, as well as any error conditions (parity, overrun, framing, or break interrupt).
[Circuit schematic source: National Semiconductor Notes]
The PC16550D is an improved version of the original 16450 Universal Asynchronous Receiver/Transmitter (UART). Functionally identical to the 16450 on powerup (CHARACTER mode)* the PC16550D can be put into an alternate mode (FIFO mode) to relieve the CPU of excessive software overhead. In this mode internal FIFOs are activated allowing 16 bytes (plus 3 bits of error data per byte in the RCVR FIFO) to be stored in both receive and transmit modes. All the logic is on chip to minimize system overhead and maximize system efficiency. Two pin functions have been changed to allow signaling of DMA transfers.
The UART performs serial-to-parallel conversion on data characters received from a peripheral device or a MODEM, and parallel-to-serial conversion on data characters received from the CPU. The CPU can read the complete status of the UART at any time during the functional operation. Status information reported includes the type and condition of the transfer operations being performed by the UART, as well as any error conditions (parity, overrun, framing, or break interrupt).
[Circuit schematic source: National Semiconductor Notes]
0 comments:
Post a Comment