
SD Host Controller Programming Model
218
September 2005
SCPS110
12.4 Status Register
The status register provides device information to the host system. All bit functions adhere to the definitions
in the PCI Local Bus Specification, as seen in the following bit descriptions. Bits in this register may be read
normally. A bit in the status register is reset when 1b is written to that bit location; a 0b written to a bit location
has no effect. See Table 123 for a complete description of the register contents.
Function 3 register offset: 06h
Register type:
Read/Clear/Update, Read-only
Default value:
0210h
BIT NUMBER
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
RESET STATE
0
1
0
1
0
Table 123. Status Register Description
BIT
FIELD NAME
TYPE
DESCRIPTION
15
PAR_ERR
RCU
Detected parity error. Bit 15 is set to 1b when either an address parity or data parity error is detected.
14
SYS_ERR
RCU
Signaled system error. Bit 14 is set to 1b when SERR is enabled and the SD host controller has signaled
a system error to the host.
13
MABORT
RCU
Received master abort. Bit 13 is set to 1b when a cycle initiated by the SD host controller on the PCI
bus has been terminated by a master abort.
12
TABORT_REC
RCU
Received target abort. Bit 12 is set to 1b when a cycle initiated by the SD host controller on the PCI
bus was terminated by a target abort.
11
TABORT_SIG
RCU
Signaled target abort. Bit 11 is set to 1b by the SD host controller when it terminates a transaction on
the PCI bus with a target abort.
109
PCI_SPEED
R
DEVSEL timing. Bits 10 and 9 encode the timing of DEVSEL and are hardwired to 01b, indicating that
the SD host controller asserts this signal at a medium speed on nonconfiguration cycle accesses.
8
DATAPAR
RCU
Data parity error detected. Bit 8 is set to 1b when the following conditions have been met:
a. PERR was asserted by any PCI device including the SD host controller.
b. The SD host controller was the bus master during the data parity error.
c. Bit 6 (PERR_EN) in the command register at offset 04h in the PCI configuration space
(see Section 12.3) is set to 1b.
7
FBB_CAP
R
Fast back-to-back capable. The SD host controller cannot accept fast back-to-back transactions;
therefore, bit 7 is hardwired to 0b.
6
UDF
R
User-definable features (UDF) supported. The SD host controller does not support the UDF; therefore,
bit 6 is hardwired to 0b.
5
66MHZ
R
66-MHz capable. The SD host controller operates at a maximum PCLK frequency of 33 MHz; therefore,
bit 5 is hardwired to 0b.
4
CAPLIST
R
Capabilities list. Bit 4 returns 1b when read, indicating that the SD host controller supports additional
PCI capabilities.
3
INT_STATUS
RU
Interrupt status. This bit reflects the interrupt status of the function. Only when bit 10 (INT_DISABLE)
in the command register (offset 04h, see Section 12.3) is a 0b and this bit is 1b, is the function’s INTx
signal asserted. Setting the INT_DISABLE bit to 1b has no effect on the state of this bit. This bit is set
only when a valid interrupt condition exists. This bit is not set when an interrupt condition exists and
signaling of that event is not enabled.
20
RSVD
R
Reserved. Bits 20 return 000b when read.