Renesas Stereo System SH7709S User Manual

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Rev. 5.00, 09/03, page 536 of 760
16.2.10
FIFO Data Count Register (SCFDR)
SCFDR is a 16-bit register which indicates the quantity of data stored in the transmit FIFO data
register (SCFTDR) and the receive FIFO data register (SCFRDR). It indicates the quantity of
transmit data in SCFTDR with the upper 8 bits, and the quantity of receive data in SCFRDR with
the lower 8 bits. SCFDR can always be read by the CPU.
Upper 8 Bits:
15
14
13
12
11
10
9
8
T4
T3
T2
T1
T0
Initial  value:
0
0
0
0
0
0
0
0
R/W:
R
R
R
R
R
R
R
R
The upper 8 bits of SCFDR indicate the quantity of non-transmitted data stored in SCFTDR. H'00
means no transmit data, and H'10 means that SCFTDR is full of transmit data.
Lower  8  Bits:
7
6
5
4
3
2
1
0
R4
R3
R2
R1
R0
Initial  value:
0
0
0
0
0
0
0
0
R/W:
R
R
R
R
R
R
R
R
The lower 8 bits of SCFDR indicate the quantity of receive data stored in SCFRDR. H'00 means
no receive data, and H'10 means that SCFRDR full of receive data.