Edmunds Gages Accu-Setter II, Руководство пользователя

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RS-232 Personal Computer
The PC Data protocol allows someone with knowledge of RS-232 communications to
write a software program to communicate to the Accu-Setter. The PC Data protocol
consists of two main categories:
1. Uploading measurement data
2. Downloading command codes
The PC is considered the Master in the system. This means that the PC must send or
request data to or from the Accu-Setter. The PC can communicate with up to ten Accu-
Setters. This is accomplished by implementing a daisy chain configuration on the Accu-
Setter’s RS-232 port. In a daisy chain configuration, each Accu-Setter must be
preprogrammed to have its own unique station number to prevent data collisions. The PC
request packet must specify the station number for the Accu-Setter that contains the
desired data.
The Accu-Setter must be in the RUN mode to communicate to any external device.
When the Master PC wants to transmit a block of data to one of several AccuSetters, it
first sends a command byte followed by a station number which identifies the target
Accu-Setter. The command byte and the station number must be transmitted using Mark
parity. The block of data that follows must be transmitted using Space parity.
The PC can determine if an Accu-Setter is online by transmitting a 2 byte packet:
EXAMPLE HEX CODE
RANGE
PC -> Accusetter 41H 30H-39H (Mark Parity)
BYTE
HEX CODE CHAR DESCRIPTION
1
st
41H A Online Request
2
nd
30H-39H 0 - 9 Station Number
If the Accu-Setter is online it will respond with a 1-byte packet:
PC <- Accu-Setter 06H