Echelon FTXL Hardware - Manual (Page 74)

66 Using the Bring-Up Application to Verify FTXL Hardware Design
LonDeassertTransceiverReset() functions write to the FTXL Transceiver reset
pin.
Status Signals
The interface includes a set of status signals that are used to determine when the
FTXL Transceiver is ready to accept data or has data to be read. The status
signal can be read using the FTXL HAL function LonTransceiverIsBusy().
When the LonTransceiverIsBusy() function reads the status register, the
FTXL_PIO component affect FTXL Transceiver pins as listed in Table 19.
Table 19. Status Signals
Signal Name FTXL Transceiver Pin Action
CS~ 31 Asserted (low)
R/W~ 30 Deasserted (high)
A0 27 Asserted (high)
D0 4 Read as status (low =
busy)
Data Register
The interface includes a bi-directional 8-bit data register. This register is used
either to:
• Write data from the Nios II processor to the FTXL Transceiver using the
FTXL HAL function LonWriteTransceiverDataRegister()
• Read data from the FTXL Transceiver using the FTXL HAL function
LonReadTransceiverDataRegister()
The register must be read or written only when LonTransceiverIsBusy() returns
FALSE.
When LonWriteTransceiverDataRegister() writes to the data register, the
FTXL_PIO component affects FTXL Transceiver pins as listed in Table 20.
Table 20. Writing to the Data Register
Signal Name FTXL Transceiver Pin Action
CS~ 31 Asserted (low)
R/W~ 30 Asserted (low)
A0 27 Deasserted (low)
D0 4
D1 3
Asserted or deasserted as
data values