Specifications

CARROLL TOUCH Chapter 4 - Smart-Frame Protocol
Touch System Programmer’s Guide 4-9
sequence to allow the touch system to establish baud rate and parity that
is used by the host.
To perform the autobaud/autoparity sequence, the host must send five
ASCII carriage returns (CR - 0DH) followed by a delay of at least
100ms after each carriage return. The touch system uses these carriage
returns to determine the baud rate used by the host. When the touch
system has determined the baud rate of the host, it stops sending breaks
to the host; the host need not send additional carriage returns after this
occurs. The simplest method, however, is for the host to send five
carriage returns with delays and ignore the breaks sent by the touch
system. This is the recommended method.
Regardless of whether or not the touch system uses autobaud/
autoparity, the host must send a Software_Reset (3CH) command
followed by a delay of at least 100ms. This clears the touch system
buffers and resets the touch system parameters listed in Table 4-6 to
their defaults. If autobaud/autoparity is being used, this also establishes
the parity being used by the host.
Checking for Touch System Errors
To confirm that the initialization sequence was successful, determine
the status of the touch system by sending the Get_Error_Report (32H)
command. The Error Report that is returned lists any errors detected by
the touch system. Since report transfer has not been enabled yet, the
host must enable it so that the touch system can transmit the Error
Report. This is accomplished by sending the Report_Transfer_On
(44H) command to the touch system before sending the
Get_Error_Report (32H) command.
Table 4-6. SFP Default Settings
System Parameters Default Setting
Touch Scanning Off
Reporting Method Coordinate reporting
Touch Mode Tracking Mode
Add Exit Point Modifier Off
Report Transfer Off
Hardware Flow Control Off