| Rev |
Log message |
Author |
Age |
Path |
| 224 |
Finished new Open8 bus record, which now includes the clock, reset and a microsecond tick. The CPU now accepts a clock and pll_locked signal, which it uses to generate the system reset in the bus record. It also contains a simple microsecond counter to feed the usec_tick in the record. This logic was removed from the real time clock and system timer entities, which now use the global version. Bus connections should be dramatically simplified, as only the read logic and interrupts are still run as separate signals. |
jshamlet |
1663d 03h |
/open8_urisc/ |
| 223 |
Added an OPEN8_BUS_TYPE record to simplify connection to Open8 modules. The CPU now passes and Open8_Bus out, which supplies the bus address, write enable, write data, and read enable. Read data and interrupts are still handled as separate signals, since they are muxed/connected at the next level up. |
jshamlet |
1663d 20h |
/open8_urisc/ |
| 222 |
Created a modified version of the epoch timer with a 32-bit, 1-uS resolution timer/comparator. |
jshamlet |
1664d 02h |
/open8_urisc/ |
| 221 |
o8_vdsm8.vhd now has a default value assigned at compile time, o8_register.vhd was cleaned up some more. |
jshamlet |
1664d 20h |
/open8_urisc/ |
| 220 |
More revision sections added |
jshamlet |
1664d 20h |
/open8_urisc/ |
| 219 |
Added revision block and corrected creation date. |
jshamlet |
1664d 21h |
/open8_urisc/ |
| 218 |
Revision sections added,
vdsm8.vhd added. |
jshamlet |
1664d 21h |
/open8_urisc/ |
| 217 |
Broke out the vdsm8 as a separate entity, since it is used in several places,
Even MORE code cleanup. |
jshamlet |
1664d 21h |
/open8_urisc/ |
| 216 |
Fixed missing parenthesis |
jshamlet |
1664d 23h |
/open8_urisc/ |
| 215 |
More code cleanup |
jshamlet |
1664d 23h |
/open8_urisc/ |
| 214 |
Initial add of some older code |
jshamlet |
1668d 21h |
/open8_urisc/ |
| 213 |
Code and comment cleanup |
jshamlet |
1668d 22h |
/open8_urisc/ |
| 212 |
Fixed issue with rewritten epoch timer not clearing alarm on set point write. |
jshamlet |
1669d 04h |
/open8_urisc/ |
| 211 |
Ok, this time with feeling. Timer should now properly reset on interval update. |
jshamlet |
1670d 02h |
/open8_urisc/ |
| 210 |
Modified the timers to reset on new interval write. This avoids an issue in the original design where the timer had to reach zero before updating, potentially causing unwanted interrupts.
Also added a flag to the CPU to allow interrupts to be processed sequentially based on the state of the I bit. This one is set to false by default, as it is a significant change in interrupt behavior. Long, and reentrant, ISRs can clear the I bit prematurely to allow themselves to be interrupted.
Lastly, added the I bit to the exported flags for possible use in memory protection schemes. |
jshamlet |
1670d 04h |
/open8_urisc/ |
| 209 |
Fixed an issue in the PIT timer that caused an immediate interrupt on interval write,
Fixed an issue in the epoch timer that resulted in a spurious interrupt due to extra LSB's being set by default in the set point register,
While cleaning elsewhere, founding a spacing issue in the CPU HDL,
Added a 4k ROM and MW core. |
jshamlet |
1670d 17h |
/open8_urisc/ |
| 208 |
Removed unnecessary package references |
jshamlet |
1671d 02h |
/open8_urisc/ |
| 207 |
Added a simple 8-bit, fixed asynchronous serial interface with compile time settable bit-rate, parity enable, and parity mode generics. |
jshamlet |
1671d 19h |
/open8_urisc/ |
| 206 |
Merged interrupt logic with other clocked process. |
jshamlet |
1675d 14h |
/open8_urisc/ |
| 205 |
More code and comment cleanup for the new SDLC engine |
jshamlet |
1675d 14h |
/open8_urisc/ |
