UART Control
From SpecNext official Wiki
| Number | $153B |
|---|---|
| Decimal | 5435 |
| Short desc. | Configuration of UART interfaces |
| Bit Mask | %0001 0101 0011 1011 |
| Readable | Yes |
| Writable | Yes |
| Subsystem | UART |
- bit 6 = 0 to select the esp uart, 1 to select the pi uart †
- bit 4 = 1 if the bits 2:0 are being written
- bits 2:0 = most significant bits of the 17-bit prescalar setting baud rate
pi gpio must be configured for uart, see Pi Peripheral Enable Register ($A0)
† either uart can be redirected to the joystick ports, see Kempston Joystick 2, Joystick I/O ($xx37 / 55)
The remaining 14-bits of prescalar value can be written by UART RX ($143B / 5179)