48 www.xilinx.com MicroBlaze Processor Reference Guide
1-800-255-7778 UG081 (v6.0) June 1, 2006
Chapter 2: MicroBlaze Signal Interface Description
On-Chip Peripheral Bus (OPB) Interface Description
The MicroBlaze OPB interfaces are implemented as byte-enable capable masters. Please
refer to the Xilinx OPB design document: “OPB Usage in Xilinx FPGA” for details.
ICache_FSL_out... IXCL_M IO Instruction side CacheLink FSL master
DCache_FSL_in... DXCL_S IO Data side CacheLink FSL slave interface
DCache_FSL_out... DXCL_M IO Data side CacheLink FSL master
Interrupt Core I Interrupt
Reset Core I Core reset, active high. Should be held
for at least 16 cycles
Clk Core I Clock
Debug_Rst Core I Reset signal from OPB JTAG UART,
Ext_BRK Core I Break signal from OPB JTAG UART
Ext_NM_BRK Core I Non-maskable break signal from OPB
Dbg_... Core IO Debug signals from OPB MDM
Valid_Instr Core O Trace: Valid instruction in EX stage
PC_Ex Core O Trace: Address for EX stage instruction
Reg_Write Core O Trace: EX stage instruction writes to the
register file
Reg_Addr Core O Trace: Destination register
MSR_Reg Core O Trace: Current MSR register value
New_Reg_Value Core O Trace: Destination register write data
Pipe_Running Core O Trace: Processor pipeline to advance
Interrup_Taken Core O Trace: Unmasked interrupt hasoccurred
Jump_Taken Core O Trace: Branch instruction evaluated true
Prefetch_Addr Core O Trace: OF stage pointer into prefetch
MB_Halted Core O Trace: Pipeline is halted
Trace_... Core O Trace signals for real time HW analysis
Table 2-1: Summary of MicroBlaze Core I/O (Continued)
Signal Interface I/O Description