
18-16
MC68SZ328 Reference Manual
MOTOROLA
Memory Stick Host Controller
18.4.4 Memory Stick Transmit FIFO Data Register
The Memory Stick Transmit FIFO Data Register is a 16-bit register. The bit position assignments for this
register are shown in the following register display. The settings for this register are described in
This register value and the FIFO pointers are initialized on power up or when the RST bit of the Memory
Stick Control/Status Register is 1.
Big- or little-endian mode of the FIFO Data Register can be set via the LEND bit of the MSC2 register.
The default setting is big-endian. When LEND is 0, the Memory Stick host controller handles the FIFO
data in big-endian mode. In big-endian mode, to send only 1 byte of data, the data byte must be written in
BSYCNT
Bits 10–8
Busy Count—This field contains the RDY timeout time setting
serial clock count (SCLK).This field is set to the maximum BSY
timeout time (set value × 4 + 2) to wait until the RDY signal is
output from the Memory Stick card.
RDY timeout error detection is not performed when
BSYCNT = 0. The initial value is 05h.
(Exceeding 5 × 4 + 2 = 22 SCLK causes an RDY timeout error.)
000 = No RDY timeout error
detection performed
001 = 1 × 4 + 2 = 6 SCLK
010 = 2 × 4 + 2 = 10 SCLK
011 = 3 × 4 + 2 = 14 SCLK
100 = 4 × 4 + 2 = 18 SCLK
101 = 5 × 4 + 2 = 22 SCLK
110 = 6 × 4 + 2 = 26 SCLK
111 = 7 × 4 + 2 = 30 SCLK
INT
Bit 7
Interrupt (Read Only)—This bit is set to 1 when an interrupt
condition is generated. Otherwise, it remains at 0 (Initial value).
The bit changes even when the INTEN bit of the MSICS
register is 0.
0 = No Interrupt generated (default)
1 = Interrupt generated
DRQ
Bit 6
DMA Request (Read Only)—This bit is set to 1 when data is
requested. Otherwise, it remains at its initial value of 0.
If the DRQEN bit of the MSDRQC register is set to 0, the
internal DMA request signal is not generated even if this DRQ
bit is 1.
0 = No DMA request generated
(default)
1 = DMA request generated
Reserved
Bits 5–4
Reserved
These bits are reserved and should
be set to 0.
RBE
Bit 3
Receive Buffer Empty Flag (Read Only)—This bit is set to 1
(initial value) when the receive data buffer is empty. It changes
to 0 when there is data in the receive data buffer.
0 = Data available in Receiver data
buffer
1 = Receiver data buffer EMPTY
(default)
RBF
Bit 2
Receive Buffer Full Flag (Read Only)—This bit is set to 1
when the receive data buffer is full. It changes to 0 when there
is space in the receive data buffer (initial value is 0).
0 = Receiver data buffer NOT FULL
(default)
1 = Receiver data buffer FULL
TBE
Bit 1
Transmit Buffer Empty Flag (Read Only)—This bit is set to 1
when the transmit data buffer is empty. It changes to 0 when
there is data in the transmit data buffer (initial value is 1).
0 = Data in the Transmit Data buffer
1 = Transmit data buffer EMPTY
(default)
TBF
Bit 0
Transmit Buffer Full Flag (Read Only)—This bit is set to1
when the transmit data buffer is full. It changes to 0 when there
is space in the transmit data buffer (initial value is 0).
0 = Transmit data buffer NOT FULL
(default)
1 = Transmit data buffer FULL
Table 18-9. Memory Stick Control/Status Register Description (Continued)
Name
Description
Setting
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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