Truth Table/Functionality
Address Operations |
|||
---|---|---|---|
arclk |
ardin |
arshft |
Function |
rising edge |
0 or 1 |
1 |
Shifts value at ardin port to the address register. |
rising edge |
don't care |
0 |
Increments the address stored in the address register by 1. |
falling edge |
don't care |
don't care |
No change. |
constant |
don't care |
don't care |
No change. |
Data Operations |
||||
---|---|---|---|---|
drclk |
drdin |
drshft |
drdout |
Function |
rising edge |
0 or 1 |
1 |
MSB of data register |
Shifts value at drdin port to the data register (LSB to MSB). |
rising edge |
don't care |
0 |
MSB of data register |
Loads data at the memory location that is pointed to in the address register value from the flash to the data register. The MSB is immediately seen on the drdout port. |
falling edge |
don't care |
don't care |
No change. |
No change. |
constant |
don't care |
don't care |
No change. |
No change. |
Control Block Operations |
|||
---|---|---|---|
program |
erase |
busy |
Function |
rising edge |
don't care |
0 -> 1 |
Programs the data contained in the data register to the address pointed to by the address register. The busy signal remains high until the program sequence is completed. The data and address registers should not be modified during this time. |
don't care |
rising edge |
0 -> 1 |
The sector indicated by the MSB of the address register is erased. |
rising edge |
don't care |
Already 1 |
Program instructions are ignored because the flash memory is already busy. |
don't care |
rising edge |
Already 1 |
Erase instructions are ignored because the flash memory is already busy. |
rising edge |
rising edge |
0 -> 1 |
The program instruction has a higher priority and is run. The erase signal is ignored. |