URL
https://opencores.org/ocsvn/open8_urisc/open8_urisc/trunk
Subversion Repositories open8_urisc
[/] [open8_urisc/] [trunk/] [Documents/] [CPU Instruction Set_files/] [sheet002.htm] - Rev 333
Go to most recent revision | Compare with Previous | Blame | View Log
<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:x="urn:schemas-microsoft-com:office:excel" xmlns="http://www.w3.org/TR/REC-html40"> <head> <meta http-equiv=Content-Type content="text/html; charset=windows-1252"> <meta name=ProgId content=Excel.Sheet> <meta name=Generator content="Microsoft Excel 12"> <link id=Main-File rel=Main-File href="../CPU%20Instruction%20Set.htm"> <link rel=File-List href=filelist.xml> <link rel=Stylesheet href=stylesheet.css> <style> <!--table {mso-displayed-decimal-separator:"\."; mso-displayed-thousand-separator:"\,";} @page {margin:.75in .7in .75in .7in; mso-header-margin:.3in; mso-footer-margin:.3in;} --> </style> <![if !supportTabStrip]><script language="JavaScript"> <!-- function fnUpdateTabs() { if (parent.window.g_iIEVer>=4) { if (parent.document.readyState=="complete" && parent.frames['frTabs'].document.readyState=="complete") parent.fnSetActiveSheet(1); else window.setTimeout("fnUpdateTabs();",150); } } if (window.name!="frSheet") window.location.replace("../CPU%20Instruction%20Set.htm"); else fnUpdateTabs(); //--> </script> <![endif]> </head> <body link=blue vlink=purple> <table border=0 cellpadding=0 cellspacing=0 width=1242 style='border-collapse: collapse;table-layout:fixed;width:932pt'> <col width=185 style='mso-width-source:userset;mso-width-alt:6765;width:139pt'> <col width=103 style='mso-width-source:userset;mso-width-alt:3766;width:77pt'> <col class=xl67 width=61 style='mso-width-source:userset;mso-width-alt:2230; width:46pt'> <col class=xl68 width=893 style='mso-width-source:userset;mso-width-alt:32658; width:670pt'> <tr height=35 style='height:26.25pt'> <td height=35 width=185 style='height:26.25pt;width:139pt'></td> <td width=103 style='width:77pt'></td> <td class=xl106 colspan=2 width=954 style='mso-ignore:colspan;width:716pt'>Open8 CPU Core Generics</td> </tr> <tr height=20 style='height:15.0pt'> <td height=20 colspan=2 style='height:15.0pt;mso-ignore:colspan'></td> <td class=xl67></td> <td class=xl68></td> </tr> <tr height=20 style='height:15.0pt'> <td height=20 class=xl69 style='height:15.0pt'>Option</td> <td class=xl69>Argument Type</td> <td class=xl70>Default</td> <td class=xl72 width=893 style='width:670pt'>Description</td> </tr> <tr height=20 style='height:15.0pt'> <td height=20 class=xl76 style='height:15.0pt;border-top:none'>Program_Start_Addr</td> <td class=xl76 style='border-top:none;border-left:none'>16-bit Address</td> <td class=xl103 style='border-top:none;border-left:none'>x"0000"</td> <td class=xl78 width=893 style='border-top:none;border-left:none;width:670pt'>Initial program counter location</td> </tr> <tr height=20 style='height:15.0pt'> <td height=20 class=xl73 style='height:15.0pt;border-top:none'>ISR_Start_Addr</td> <td class=xl73 style='border-top:none;border-left:none'>16-bit Address</td> <td class=xl74 style='border-top:none;border-left:none'>x"FFF0"</td> <td class=xl75 width=893 style='border-top:none;border-left:none;width:670pt'>Sets the initial location of the interrupt vector table</td> </tr> <tr height=20 style='height:15.0pt'> <td height=20 class=xl76 style='height:15.0pt;border-top:none'>Stack_Start_Addr</td> <td class=xl76 style='border-top:none;border-left:none'>16-bit Address</td> <td class=xl103 style='border-top:none;border-left:none'>x"03FF"</td> <td class=xl78 width=893 style='border-top:none;border-left:none;width:670pt'>Initial location of the CPU Stack - Must be located in accessible RAM</td> </tr> <tr height=40 style='height:30.0pt'> <td height=40 class=xl73 style='height:30.0pt;border-top:none'>Allow_Stack_Address_Move</td> <td class=xl73 style='border-top:none;border-left:none'>Boolean</td> <td class=xl74 style='border-top:none;border-left:none'>FALSE</td> <td class=xl75 width=893 style='border-top:none;border-left:none;width:670pt'>If false, the RSP instruction will reset the stack pointer to "Stack_Start_Addr" by default. If true, the RSP instruction will either allow the stack pointer to be loaded from R1:R0 or copied to R1:R0 depending on the status of the PSR_GP4 (PSR_S) flag.</td> </tr> <tr height=80 style='height:60.0pt'> <td height=80 class=xl107 style='height:60.0pt;border-top:none'>Enable_Auto_Increment</td> <td class=xl107 style='border-top:none;border-left:none'>Boolean</td> <td class=xl108 style='border-top:none;border-left:none'>FALSE</td> <td class=xl109 width=893 style='border-top:none;border-left:none;width:670pt'>If true, indexed instructions such as LDX, LDO, STX, STO will automatically post-increment if an odd register is specified. The effect is similar to a normal indexed instruction followed by an UPP instruction on the same register pair. For example, LDX R5 (or LDX R4++) will result in R0 getting the data stored at the address specified by R5:R4. Afterwards, the register pair R5:R4 will be incremented by 1, possibly setting the PSR_C flag. If false, specifying either register in a register pair will result in normal behavior.</td> </tr> <tr height=60 style='height:45.0pt'> <td height=60 class=xl73 style='height:45.0pt;border-top:none'>BRK_Implements_WAI</td> <td class=xl73 style='border-top:none;border-left:none'>Boolean</td> <td class=xl74 style='border-top:none;border-left:none'>FALSE</td> <td class=xl75 width=893 style='border-top:none;border-left:none;width:670pt'>If true, the BRK instruction will cause the processor to halt as if an INT instruction was executed, but without triggering an interrupt. This is useful for pausing the CPU until an interrupt occurs. If false, the BRK instruction flushes the pipeline and executes an extended (5-clock) NOP cycle.</td> </tr> <tr height=20 style='height:15.0pt'> <td height=20 class=xl107 style='height:15.0pt;border-top:none'>Enable_NMI</td> <td class=xl107 style='border-top:none;border-left:none'>Boolean</td> <td class=xl108 style='border-top:none;border-left:none'>TRUE</td> <td class=xl109 width=893 style='border-top:none;border-left:none;width:670pt'>Forces bit 0 of the Interrupt Mask to 1, causing Interrupt 0 to be non-maskable.</td> </tr> <tr height=40 style='height:30.0pt'> <td height=40 class=xl73 style='height:30.0pt;border-top:none'>Sequential_Interrupts</td> <td class=xl73 style='border-top:none;border-left:none'>Boolean</td> <td class=xl74 style='border-top:none;border-left:none'>FALSE</td> <td class=xl75 width=893 style='border-top:none;border-left:none;width:670pt'>Prohibits interrupts from initiating an ISR if the I-bit is set, making ISRs sequential. This potentially blocks interrupt priority by allowing a lower level interrupt to block a higher level interrupt. This can be worked around by clearing the I-bit in known interruptable ISRs.</td> </tr> <tr height=40 style='height:30.0pt'> <td height=40 class=xl107 style='height:30.0pt;border-top:none'>RTI_Ignores_GP_Flags</td> <td class=xl107 style='border-top:none;border-left:none'>Boolean</td> <td class=xl108 style='border-top:none;border-left:none'>FALSE</td> <td class=xl109 width=893 style='border-top:none;border-left:none;width:670pt'>If set, preserves the general purpose flags GP_PSR4 (PSR_S) to GP_PSR7 on ISR exit, allowing them to be persistently set by interrupts. The lower four flag bits are always restored.</td> </tr> <tr height=40 style='height:30.0pt'> <td height=40 class=xl73 style='height:30.0pt;border-top:none'>Supervisor_Mode</td> <td class=xl73 style='border-top:none;border-left:none'>Boolean</td> <td class=xl74 style='border-top:none;border-left:none'>FALSE</td> <td class=xl75 width=893 style='border-top:none;border-left:none;width:670pt'>If set to true, enables restrictions on RSP, CLP/STP, and SMSK where they only can alter internal registers if the I bit is set. Also initializes the CPU to start with the I-bit set. If set to false, there are no restrictions on these instructions.</td> </tr> <tr height=20 style='height:15.0pt'> <td height=20 class=xl107 style='height:15.0pt;border-top:none'>Unsigned_Index_Offsets</td> <td class=xl107 style='border-top:none;border-left:none'>Boolean</td> <td class=xl108 style='border-top:none;border-left:none'>FALSE</td> <td class=xl109 width=893 style='border-top:none;border-left:none;width:670pt'>Determines whether the offset calculation for LDO/STO is signed or unsigned. Default behavior is signed.</td> </tr> <tr height=40 style='height:30.0pt'> <td height=40 class=xl107 style='height:30.0pt;border-top:none'>Rotate_Ignores_Carry</td> <td class=xl107 style='border-top:none;border-left:none'>Boolean</td> <td class=xl108 style='border-top:none;border-left:none'>FALSE</td> <td class=xl109 width=893 style='border-top:none;border-left:none;width:670pt'>By default, the V8 uRISC processor included the carry in rotations, making them effectively 9-bit rotations. This generic modifies the ALU such that the rotations work as classically defined and do NOT involve, or alter, the carry bit.</td> </tr> <tr height=20 style='height:15.0pt'> <td height=20 class=xl73 style='height:15.0pt;border-top:none'>Default_Interrupt_Mask</td> <td class=xl73 style='border-top:none;border-left:none'>8-bit Data</td> <td class=xl74 style='border-top:none;border-left:none'>x"FF"</td> <td class=xl75 width=893 style='border-top:none;border-left:none;width:670pt'>Sets the initial interrupt mask (note that bit 0 is ignored if Enable_NMI is set TRUE)</td> </tr> <tr height=20 style='height:15.0pt'> <td height=20 class=xl107 style='height:15.0pt;border-top:none'>Clock_Frequency</td> <td class=xl107 style='border-top:none;border-left:none'>Real</td> <td class=xl108 style='border-top:none;border-left:none'>-</td> <td class=xl109 width=893 style='border-top:none;border-left:none;width:670pt'>Clock frequency in Hz of the CPU clock. Used to configure the 1Mhz/1uSec tick pulse</td> </tr> <![if supportMisalignedColumns]> <tr height=0 style='display:none'> <td width=185 style='width:139pt'></td> <td width=103 style='width:77pt'></td> <td width=61 style='width:46pt'></td> <td width=893 style='width:670pt'></td> </tr> <![endif]> </table> </body> </html>
Go to most recent revision | Compare with Previous | Blame | View Log