Serial Connection Requirements, Windows NT v3.10c Driver
The Windows NT v3.10c driver normally
requires the
following serial connections:
| Acronym |
Signal
Name |
Signal
Function |
DB9 Pin # |
| RD |
Receive |
Controller transmit |
2 |
| TD |
Transmit |
Computer Transmit |
3 |
| Gnd |
Ground |
Ground |
5 |
| DSR |
Data Set Ready |
Controller has power |
6 |
| CTS |
Clear to Send |
Controller Power On
Self-Test (POST) complete |
8 |
- Touchscreen data is sent on Rd, and ground is
always needed as a reference.
- DSR is used to indicate to the computer that the
controller has power.
- CTS is used to indicate to the computer that the
controller has passed its Power On Self-Test.
- The latter two are checked
when the driver
instructs the computer to ask the controller for its Power On Self-Test results; this
command is sent on the Td line.
- The driver will load, but the
touchscreen will not function under ANY of the following conditions:
- The POST results are not received by the computer;
- Controller power is not indicated by DSR being
high;
- POST completion is not indicated by CTS being
high.
- If a wire is broken, or only a two wire connection
is being used (Rd and Gnd), it will be necessary to disable
the POST results check (commonly referred to as "disabling
handshaking") before the touchscreen can function. See
"Disabling hardware handshaking."
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