| 2010,26 → 2010,45 |
|---|
| * eax = -1 for incorrect ebx |
| |
| ====================================================================== |
| ==================== Function 42 - read IRQ data. ==================== |
| ==================== Function 42 - work with IRQ data. =============== |
| ====================================================================== |
| |
| ------------------------ Reading data -------------------------------- |
| |
| When an IRQ occurs, the system reads data from ports indicated |
| earlier by function 44 and writes this data to |
| internal buffer. This function reads out data from that buffer |
| bytewise. |
| to the buffer specified as parameter. |
| Parameters: |
| * eax = 42 - function number |
| * ebx = IRQ number, 0..15 |
| Returned value: (use value of ecx to distinguish) |
| * bl = IRQ number, 0..15 |
| * bh = subfunction number, 0 |
| Other part of register ebx, must be zero. |
| * ecx = pointer to the receive buffer |
| Returned value: (use value of eax to distinguish) |
| * if the thread is not IRQ owner (or IRQ number is incorrect): |
| * ecx = 2 |
| * eax = -1 |
| * if there is no data: |
| * eax = 0 |
| * ecx = 1 |
| * ebx destroyed |
| * if all is ok: |
| * eax = byte size of data, not yet read from buffer |
| * ecx = 0 |
| * ebx = current byte |
| * eax = byte size of data, read from buffer |
| |
| See remarks below. |
| |
| ------------------------ Get data size ------------------------------- |
| |
| Parameters: |
| * eax = 42 - function number |
| * bl = IRQ number, 0..15 |
| * bh = subfunction number, 0 |
| Other part of register ebx, must be zero. |
| * ecx = pointer to receive buffer |
| Returned value: (use value of eax to distinguish) |
| * if the thread is not IRQ owner (or IRQ number is incorrect): |
| * eax = -1 |
| * if all is ok: |
| * eax = byte size of data in buffer |
| |
| Remarks: |
| * Previously the thread must reserve indicated IRQ for itself |
| by function 45. |