
14.PMC CONTROL FUNCTION B-63783EN-1/01
- 1470 -
14.2 EXTERNAL DATA INPUT
General
Data can be input and output between CNC and PMC, using signals
such as the following:
External data input External data output
Input signal Output signal Input signal Output signal
Address signal
EIA0-EIA7 EOA0-EOA7
Data signal
EID0-EID47 EOD0-EOD47
Data output
request signal
ERDRQ
Strobe signal
EISTB EOSTB
Read completion
signal
EIREND EOREND
Search signal
ESEND
External data input and external data output are roughly symmetrical.
External data input sends data from the PMC to the CNC, whereas
external data output sends data from the CNC to the PMC. Before
external data output, a request for data must be sent from the PMC to
the CNC, using external data input.
- Basic procedure for external data input
The basic external data input procedure is described below:
1. The PMC sets address signals EIA0 to EIA7 that indicate the data
type and data signals EID0 to EID47. Data output request signal
ERDRQ must always be set to "0."
2. he PMC sets strobe signal EISTB to "1".
3. When the EISTB signal is set to "1", the control unit reads the
address, data, and data output request.
4. After reading the address, the control unit sets read completion
signal EIREND to "1".
5. When the EIREND signal is set to "1", the PMC sets the EISTB
signal to 0.
6. When the EISTB signal is set to "0", the control unit sets the
EIREND signal to 0.
This completes the data input procedure. New data can now be
entered.
The timing diagram is shown below:
ddress signal
Data signal
Data output signal
Strobe signal
Data input (NC)
Input end signal
EIA0 to 7
EID0 to 47
ERDRQ
EISTB
EIREND
(1) (2) (3) (4) (5) (6)
“0”