6502/CLK
1
0
Fork 0
mirror of https://github.com/TomHarte/CLK.git synced 2025-08-15 14:27:29 +00:00
Code Issues Projects Releases Wiki Activity

Switches to proper SCSI terminology and better attempts a command phase.

Browse Source
This commit is contained in:
Thomas Harte
2019-08-18 15:10:07 -04:00
parent 0e0c789b02
commit 8339e2044c
2 changed files with 14 additions and 10 deletions
Download Patch File Download Diff File Expand all files Collapse all files

16
Components/5380/DirectAccessDevice.cpp
View File

@@ -25,26 +25,30 @@ void DirectAccessDevice::scsi_bus_did_change(Bus *, BusState new_state) {
time." time."
*/ */
switch(state_) { switch(phase_) {
case State::Inactive: case Phase::AwaitingSelection:
if( if(
(new_state & scsi_id_mask_) && (new_state & scsi_id_mask_) &&
((new_state & (Line::SelectTarget | Line::Busy | Line::Input)) == Line::SelectTarget) ((new_state & (Line::SelectTarget | Line::Busy | Line::Input)) == Line::SelectTarget)
) { ) {
state_ = State::Selected; phase_ = Phase::Command;
bus_state_ |= Line::Busy | Line::Request; bus_state_ |= Line::Busy | Line::Request | Line::Control; // Initiate the command phase: request a command byte.
bus_.set_device_output(scsi_bus_device_id_, bus_state_); bus_.set_device_output(scsi_bus_device_id_, bus_state_);
} }
break; break;
case State::Selected: case Phase::Command:
switch(new_state & (Line::Request | Line::Acknowledge)) { switch(new_state & (Line::Request | Line::Acknowledge)) {
// If request and acknowledge are both enabled, grab a byte and cancel the request.
case Line::Request | Line::Acknowledge: case Line::Request | Line::Acknowledge:
bus_state_ &= ~Line::Request; bus_state_ &= ~Line::Request;
printf("Got %02x maybe?\n", bus_state_ & 0xff); printf("Got %02x maybe?\n", bus_state_ & 0xff);
// TODO: is the command phase over?
break; break;
case Line::Acknowledge: // The reset of request has caused the initiator to reset acknowledge, so it is now
// safe to request the next byte.
case 0: case 0:
bus_state_ |= Line::Request; bus_state_ |= Line::Request;
break; break;

8
Components/5380/DirectAccessDevice.hpp
View File

@@ -32,10 +32,10 @@ class DirectAccessDevice: public Bus::Observer {
const BusState scsi_id_mask_; const BusState scsi_id_mask_;
const size_t scsi_bus_device_id_; const size_t scsi_bus_device_id_;
enum class State { enum class Phase {
Inactive, AwaitingSelection,
Selected Command
} state_ = State::Inactive; } phase_ = Phase::AwaitingSelection;
BusState bus_state_ = DefaultBusState; BusState bus_state_ = DefaultBusState;
}; };