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PCI Bus Controller
22-16
Freescale Semiconductor
22.3.2.2
Target Base Address Translation Register 0 (PCITBATR0)
The next two registers, PCITBATR0 and PCITBATR1, are aliases for the registers at address
0xFC0A_8090 and 0xFC0A_8094 respectively. When these registers are written to, it also updates the
contents of the other PCITBATR0 and PCITBATR1 registers. Likewise, when PCITBATR0 at address
18–16
PRGDIV
Programmable clock divide. Stores programmable internal bus clock to external PCI clock divide ratio. When
this bit field is non-zero, this ratio has priority over the auto-detected clock ratio indicated in the AUTODIV field.
When set to a reserved setting, PCI controller could malfunction. Software can revert back to the
auto-detected divide ratio by clearing this bit field.
000 Ignore bit field and use AUTODIV
001 Divide by 1
010 Divide by 2
011 Divide by 3
100 Divide by 4
101 Divide by 5
110 Divide by 1.5 (Multiply by
2
/
3
)
111 Reserved
15
DRDE
Delayed read discarded enable. Enables CPU interrupt generation when delayed read buffer is discarded
because the request was not retried by the external PCI master in under 2
15
PCI clock cycles. When enabled
and the above condition occurs, software must clear PCIGSCR[DRD] to clear the interrupt condition.
0 Interrupt disabled
1 Interrupt enabled
14
Reserved, must be cleared.
13
PEE
PERR detected interrupt enable. Enables CPU interrupt generation when a PCI parity error is detected on the
PCI_PERR signal. When enabled and PCI_PERR asserts, software must clear PCIGSCR[PE] to clear the
interrupt condition.
0 Interrupt disabled
1 Interrupt enabled
12
SEE
SERR detected interrupt enable. Enables CPU interrupt generation when a PCI system error is detected on
the PCI_SERR signal. When enabled and PCI_SERR asserts, software must clear PCIGSCR[SE] to clear the
interrupt condition.
0 Interrupt disabled
1 Interrupt enabled
11
ERE
Error response interrupt enable. Enables CPU interrupt generation when an error response is detected on the
internal crossbar switch bus when a PCI target transaction is attempted. When enabled and an internal error
occurs, software must clear the PCIGSCR[ER] status bit to clear the interrupt condition.
0 Interrupt disabled
1 Interrupt enabled
10–1
Reserved, must be cleared.
0
PR
PCI reset. Controls the external PCI_RST signal. When this bit is cleared, external PCI_RST deasserts.
Setting this bit when clear generates a strobe to some of the internal logic to return it to its reset value. It resets
all PCI Type 0 configuration registers and resets the internal PCI_AD[31:0], PCI_PAR, and PCI_CBE[3:0]
output lines. If grant to the PCI controller is asserted in the cycle after the reset strobe generates, the external
PCI_AD[31:0], PCI_PAR, and PCI_CBE[3:0] pins are driven low. The application software must not initiate PCI
transactions while this bit is set. It is recommended that this bit is programmed last during initialization.
The reset value of the bit is 1 (PCI_RST asserted).
Table 22-11.
PCIGSCR Field Descriptions (continued)
Field
Description
Summary of Contents for MCF54455
Page 33: ...xxviii Freescale Semiconductor ...
Page 67: ...Freescale Semiconductor 1 ...
Page 125: ...Freescale Semiconductor 1 ...
Page 145: ...Enhanced Multiply Accumulate Unit EMAC 5 21 Freescale Semiconductor ...
Page 173: ...Cache 6 28 Freescale Semiconductor ...
Page 179: ...Static RAM SRAM 7 6 Freescale Semiconductor ...
Page 207: ...Power Management 9 16 Freescale Semiconductor ...
Page 323: ...Reset Controller Module 13 8 Freescale Semiconductor ...
Page 389: ...Pin Multiplexing and Control 16 44 Freescale Semiconductor ...
Page 575: ...PCI Bus Controller 22 58 Freescale Semiconductor ...
Page 600: ...Advanced Technology Attachment ATA Freescale Semiconductor 23 25 ...
Page 601: ...Freescale Semiconductor 1 ...
Page 842: ...I2 C Interface Freescale Semiconductor 33 16 ...
Page 843: ...Freescale Semiconductor 1 ...
Page 921: ...Revision History A 6 Freescale Semiconductor ...