3M M2256PW User Manual - Page 25

3M™ Display M2256PW User Guide 25 POC Status - The status of the Power-on Checks. Various controller systems are checked at power-up. If any failures in these systems are detected, a POC flag is set. The POC status field reports the state of these flags. Table 7. Power On Check Bit Fields Bit Number 0 1 2 3 4 5--7 Description Not used ROM_ERROR PWM Error NOV_ERROR HDW_ERROR Not used Notes Code area checksum error Touch screen not connected or potential problem Parameter blocks checksum error Problem with ADCs Cmd Status - The status for the last command request. This field is used to determine whether the last request was processed successfully. It is also used to track the progress of a multi-stage request, such as 2 point calibration. The Status Request does not affect the contents of this field, i.e., successful or unsuccessful processing of a previous status request does not cause the command status field to be updated. Table 8. Valid Command Status Field Entries Response 0 1 2 3 4 5 6 -- 7 Description Failure in command processing Command being processed Stage 1 processing complete (for multi-stage commands) Command complete Soft Reset Occurred Hard Reset Occurred Not used Get Feature - GetMaxCount This is a request to send information that indicates the maximum number of simultaneous touches supported by the controller. Table 9. Setup Stage Offset 0 1 2 Field bmRequestType bRequest wValue 4 wIndex 6 wLength Size 1 1 2 2 2 Value 0xA1 0x01 0x0312 0 2 Description Class,D2H,Interface Get Report msb=03=Feature lsb=12 Feature Report ID Always 0 Always 2 3M Touch Systems, Inc. Proprietary Information