User's Manual

FLC-BTM805 Datasheet
Flaircomm Microelectronics Confidential
-27-
When BTM805 is connected to another digital device, UART_RX and UART_TX transfer data
between the two devices. The remaining 2 signals, UART_CTS and UART_RTS, implement RS232
hardware flow control where both are active low indicators.
If UART_CTS and UART_RTS are not required for hardware flow control, they are reconfigurable
as PIO.
UART configuration parameters, such as baud rate and packet format, are set using BTM805
firmware.
Note:
To communicate with the UART at its maximum data rate using a standard PC, an accelerated serial port
adapter card is required for the PC.
Parameter
Possible Values
Baud Rate
Minimum
1200 baud (≤2%Error)
9600 baud (≤1%Error)
Maximum
4M baud (≤1%Error)
Flow control
RTS/CTS or None
Parity
None, Odd or Even
Number of Stop Bits
1 or 2
Bits per Byte
8
Table 15: Possible UART Settings
4.6.2 UART Configuration While Reset is Active
The UART interface for BTM805 is a tri-state while the chip is being held in reset. This enables the
user to daisy chain devices onto the physical UART bus. This constraint on this method is that any
devices connected to this bus must tri-state when BTM805 reset is de-asserted and the firmware
begins to run.