UART/IrDA Control and Status Registers
12-56
Table 12–47. FIFO Control (FCR) Register
Bit
Name
Value
Function
R/W
Reset
Value
7–6
RX_FIFO_TRIG
Sets the trigger level for the RX FIFO:
If SCR7 = 0 and TLR7:4 = 0000:
W
00
00
8 characters
01
16 characters
10
56 characters
11
60 characters
If SCR7 = 0 and TLR7:4
0
0000,
RX_FIFO_TRIG is not considered.
1
RX_FIFO_TRIG is two LSBs of the trigger
level (1-63 on 6 bits) with granularity of 1.
5–4
TX_FIFO_TRIG
Sets the trigger level for the TX FIFO:
If SCR6 = 0 and TLR3:0 = 0000:
00: 8 spaces
01: 16 spaces
10: 32 spaces
11: 56 spaces
W
00
00
8 characters
01
16 characters
10
56 characters
11
60 characters
If SCR6=1, TX_FIFO_TRIG is two LSBs of
the trigger level (1-63 on 6 bits) with
granularity of 1.
Notes:
1) Bits 4 and 5 can only be written when EFR[4] = 1.
2) Bits 0 to 3 can be changed only when baud clock is not running (DLL and DLH set to 0).
3) See Table 12–36 for FCR[5:4] setting restriction when SCR[6] = 1.
4) See Table 12–37 for FCR[7:6] setting restriction when SCR[7] = 1.