Rev |
Log message |
Author |
Age |
Path |
190 |
Fixed a bug in CPU where RTI/RTS wasn't idling the instruction cache, causing intermittent failures where RTI would execute as RTS, corrupting the stack;
Fixed a bug in the real-time clock where the uSec tick generator would stop if the PIT timer value was left/set to 0x00. |
jshamlet |
1587d 00h |
/open8_urisc/ |
189 |
Merged changes from private repository,
added ceil_log2 function to Open8_pkg, since it is used to calculate RAM vectors,
cleaned up comments and removed local copies of the ceil_log2 function from peripherals. |
jshamlet |
1588d 01h |
/open8_urisc/ |
188 |
Added a generic to alter the behavior of RTI so that it can optionally skip restoring the general purpose flags GP4 to GP7, allowing ISR's to make persistent changes to them. Also exported these flags to the top level for use outside the CPU. |
jshamlet |
1588d 03h |
/open8_urisc/ |
187 |
Added the CPU_Halt input, only now as an input to the instruction decoder. The CPU_Halt line will assert the registered CPU_Halt_Req, which will cause the instruction decoder to abort the current instruction, reset the PC, then enter a hold state until the line is deasserted. Additionally, a very minor bug that could cause the SMSK instruction to effectively execute twice if interrupted was fixed. Lastly, cleaned up the comments even more. |
jshamlet |
1590d 00h |
/open8_urisc/ |
186 |
Merged the interrupt override logic into the case structure, simplifying how interrupts are processed. |
jshamlet |
1593d 00h |
/open8_urisc/ |
185 |
1) Fixed an apparently long-standing bug where the interrupt bit wasn't being cleared after an RTI
2) Modified the program counter logic to be simpler. It now always increments, and states control the increment using the offset field. A new set of constants was added to replace the old states.
3) Modified the ALU to always use Operand1 instead of ALU_Ctrl.Data (and removed the field in the record). A new ALU command, ALU_GMSK, was added, as it was the only instruction to set the .Data field to something other than Operand1 (Int_Mask)
4) Modified the package file so that flag names match what the assembler calls them. FL_Z is now PSR_Z, FL_GP1 is now PSR_GP4, etc.
5) Cleaned up the comments and code formatting |
jshamlet |
1593d 02h |
/open8_urisc/ |
184 |
More file/entity renaming to match private versions. |
jshamlet |
1595d 02h |
/open8_urisc/ |
183 |
Renamed core to o8_cpu to match new naming scheme |
jshamlet |
1595d 03h |
/open8_urisc/ |
182 |
Simplified the address generation logic at the expense of making LDX take one additional clock cycle. This allowed the address logic to be split out of the main state machine and simplified (greatly). During this process, a bug in SDO was found and fixed that caused it to return through the wrong pipe fill state wnen auto increment was disabled. |
jshamlet |
1595d 03h |
/open8_urisc/ |
181 |
Altered the RSP instruction to allow the stack pointed to either be restored from registers or stored to registers based on the status of a processor bit. Also modified LDX to simplify the address logic. |
jshamlet |
1595d 23h |
/open8_urisc/ |
180 |
Added additional Open8 compatible modules |
jshamlet |
1600d 03h |
/open8_urisc/ |
179 |
Replacing files accidentally deleted during check-in |
jshamlet |
1609d 22h |
/open8_urisc/ |
178 |
Adding Open8 toolset for pure assembly |
jshamlet |
1609d 23h |
/open8_urisc/ |
177 |
Fixed comments in RTC module |
jshamlet |
2920d 03h |
/open8_urisc/ |
176 |
Fixed documentation errors,
Modified uSec_Tick such that it is always generated regardless of the interval. |
jshamlet |
2925d 01h |
/open8_urisc/ |
175 |
Added 4 and 8-bit LCD interfaces with backlight and contrast DACs |
jshamlet |
2925d 05h |
/open8_urisc/ |
174 |
Added ROM/RAM wrappers |
jshamlet |
3120d 00h |
/open8_urisc/ |
173 |
Added a couple of useful interfaces for detecting button presses and clock changes. |
jshamlet |
3120d 00h |
/open8_urisc/ |
172 |
General code cleanup |
jshamlet |
3120d 01h |
/open8_urisc/ |
171 |
Fixed comments for offsets 0x0 - 0x3 to indicate the read value |
jshamlet |
3120d 01h |
/open8_urisc/ |