/// <summary>
/// Ask all of the devices on the VPW bus for permission to switch to 4X speed.
/// </summary>
private async Task <List <byte> > RequestHighSpeedPermission(ToolPresentNotifier notifier)
{
Message permissionCheck = this.protocol.CreateHighSpeedPermissionRequest(DeviceId.Broadcast);
await this.device.SendMessage(permissionCheck);
// Note that as of right now, the AllPro only receives 6 of the 11 responses.
// So until that gets fixed, we could miss a 'refuse' response and try to switch
// to 4X anyhow. That just results in an aborted read attempt, with no harm done.
List <byte> result = new List <byte>();
Message response = null;
bool anyRefused = false;
while ((response = await this.device.ReceiveMessage()) != null)
{
this.logger.AddDebugMessage("Parsing " + response.GetBytes().ToHex());
Protocol.HighSpeedPermissionResult parsed = this.protocol.ParseHighSpeedPermissionResponse(response);
if (!parsed.IsValid)
{
await Task.Delay(100);
continue;
}
result.Add(parsed.DeviceId);
if (parsed.PermissionGranted)
{
this.logger.AddUserMessage(string.Format("Module 0x{0:X2} ({1}) has agreed to enter high-speed mode.", parsed.DeviceId, DeviceId.DeviceCategory(parsed.DeviceId)));
// Forcing a notification message should help ELM devices receive responses.
await notifier.ForceNotify();
await Task.Delay(100);
continue;
}
this.logger.AddUserMessage(string.Format("Module 0x{0:X2} ({1}) has refused to enter high-speed mode.", parsed.DeviceId, DeviceId.DeviceCategory(parsed.DeviceId)));
anyRefused = true;
}
if (anyRefused)
{
return(null);
}
return(result);
}
/// <summary>
/// Does everything required to switch to VPW 4x
/// </summary>
public async Task <bool> VehicleSetVPW4x(VpwSpeed newSpeed, ToolPresentNotifier notifier)
{
if (!device.Supports4X)
{
if (newSpeed == VpwSpeed.FourX)
{
// where there is no support only report no switch to 4x
logger.AddUserMessage("This interface does not support VPW 4x");
}
return(true);
}
// Configure the vehicle bus when switching to 4x
if (newSpeed == VpwSpeed.FourX)
{
logger.AddUserMessage("Attempting switch to VPW 4x");
await device.SetTimeout(TimeoutScenario.ReadProperty);
// The list of modules may not be useful after all, but
// checking for an empty list indicates an uncooperative
// module on the VPW bus.
List <byte> modules = await this.RequestHighSpeedPermission(notifier);
if (modules == null)
{
// A device has refused the switch to high speed mode.
return(false);
}
Message broadcast = this.protocol.CreateBeginHighSpeed(DeviceId.Broadcast);
await this.device.SendMessage(broadcast);
// Check for any devices that refused to switch to 4X speed.
// These responses usually get lost, so this code might be pointless.
Message response = null;
while ((response = await this.device.ReceiveMessage()) != null)
{
Response <bool> refused = this.protocol.ParseHighSpeedRefusal(response);
if (refused.Status != ResponseStatus.Success)
{
// This should help ELM devices receive responses.
await notifier.ForceNotify();
continue;
}
if (refused.Value == false)
{
// TODO: Add module number.
this.logger.AddUserMessage("Module refused high-speed switch.");
return(false);
}
}
}
else
{
logger.AddUserMessage("Reverting to VPW 1x");
}
// Request the device to change
await device.SetVpwSpeed(newSpeed);
TimeoutScenario scenario = newSpeed == VpwSpeed.Standard ? TimeoutScenario.ReadProperty : TimeoutScenario.ReadMemoryBlock;
await device.SetTimeout(scenario);
return(true);
}