CN8478 Datasheet, PDF (55/221 Pages) Conexant Systems, Inc – Multichannel Synchronous Communications Controller (MUSYCC)

CN8478/CN8474A/CN8472A/CN8471A
Multichannel Synchronous Communications Controller (MUSYCC™)
2.0 Host Interface
2.2 PCI Configuration Registers
Register 15, Address 3Ch
Table 2-16. Register 15, Address 3Ch
Bit
Field
Name
Reset
Value
Type
Description
31:16 Reserved
0 RO
Unused.
15:8
Interrupt Pin
02h RO
Defines which PCI interrupt pin Function 1 uses. 02h means
MUSYCC uses pin INTB* for interrupts sourced by devices
connected to EBUS.
7:0
Interrupt Line
0 RW
Communicates interrupt line routing. System initialization
software writes a value to this register indicating which host
interrupt controller input is connected to MUSYCC’s INTB* pin.
NOTE(S): An active-low signal is denoted by a trailing asterisk (*).
2.2.3 PCI Reset
MUSYCC resets all internal functions when it detects the assertion of the PRST*
signal line. Upon reset, the following occurs:
• All PCI output signals go to three-state immediately and asynchronously
with respect to the PCI clock input, PCLK.
• All EBUS output signals go to three-state immediately and asynchronously
with respect to the EBUS clock output, ECLK.
• All writable register bits are set to 0.
• All PCI data transfers terminate immediately.
• All serial data transfers terminate immediately.
• MUSYCC disables and responds only to PCI configuration cycles.
2.2.4 Host Interface
After a hardware reset, the PCI configuration space within MUSYCC needs to be
configured by the host with the following information:
For Function 0:
• Base address register
• Fast back-to-back enable/disable
• SERR* signal driver enable/disable
• Parity error response enable/disable
• Bus mastering enable/disable
• Memory space access enable/disable
For Function 1:
• Base address register
• Parity error response enable/disable
• Memory space access enable/disable
Function 0 provides services to the serial interfaces in MUSYCC; Function 1
provides services to the EBUS interface in MUSYCC.
After the configuration spaces are configured, MUSYCC can master the PCI
bus or provide slave-mode access to the host.
100660E
Conexant
2-17