Texas Instruments Dual/Single Socket CardBus and UntraMedia Controller PCI7621 - Manual (Page 276)

13−4
13.4 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 a 1 is written to that bit location; a 0 written to a bit location has no effect. See
Table 13−3 for a complete description of the register contents.
Bit 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Name Status
Type RCU RCU R R RCU R R R R R R R RU R R R
Default 0 0 0 0 0 0 1 0 0 0 0 1 0 0 0 0
Register: Status
Offset: 06h
Type: Read/Clear/Update, Read-only
Default: 0210h
Table 13−3. Status Register Description
BIT FIELD NAME TYPE DESCRIPTION
15 PAR_ERR RCU Detected parity error. Bit 15 is set to 1 when either an address parity or data parity error is detected.
14 SYS_ERR RCU Signaled system error. Bit 14 is set to 1 when SERR is enabled and the Smart Card controller has
signaled a system error to the host.
13 MABORT R This function does not support bus mastering. This bit is hardwired to 0.
12 TABT_REC R This function does not support bus mastering and never receives a target abort. This bit is hardwired
to 0.
11 TABT_SIG RCU Signaled target abort. Bit 11 is set to 1 by the Smart Card controller when it terminates a transaction
on the PCI bus with a target abort.
10−9 PCI_SPEED R DEVSEL timing. Bits 10 and 9 encode the timing of DEVSEL and are hardwired to 01b, indicating that
the Smart Card controller asserts this signal at a medium speed on nonconfiguration cycle accesses.
8 DATAPAR R This function does not support bus mastering. This bit is hardwired to 0.
7 FBB_CAP R Fast back-to-back capable. The Smart Card controller cannot accept fast back-to-back transactions;
therefore, bit 7 is hardwired to 0.
6 RSVD R Reserved. Bit 6 returns 0 when read.
5 66MHZ R 66-MHz capable. The Smart Card controller operates at a maximum PCLK frequency of 33 MHz;
therefore, bit 5 is hardwired to 0.
4 CAPLIST R Capabilities list. Bit 4 returns 1 when read, indicating that the Smart Card controller supports additional
PCI capabilities. The linked list of PCI power-management capabilities is implemented in this function.
3 INT_STAT RU Interrupt status. This bit reflects the interrupt status of the function. Only when bit 10 (INT_DISABLE)
in the command register (see Section 11.3) is a 0 and this bit is 1, is the function’s INTx signal asserted.
Setting the INT_DISABLE bit to 1 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.
2−0 RSVD R Reserved. Bits 3−0 return 0s when read.