CY545 Stepper System Controller
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DIP
PLCC
Pin Name
Description
9
10
11
12
13
(I)
RESET
RxD
NC
CY545 hardware reset, active high pulse
Received serial data into CY545
No connection
10
-
(I)
(O)
(O)
11
TxD
Transmitted serial data from CY545
These are TTL level serial data signals that can be used to issue
commands to or get replies from the CY545. Addition of an RS-232
voltage level driver/receiver, such as the Maxim MAX233, allows any RS-
232 device, such as the IBM PC COM1 port to talk directly to the CY545.
DIP
12
PLCC
14
Pin Name
SW_SEL/
Description
Switch select
(O)
(I)
This signal is active when the CY545 is reading a parameter value from
external thumbwheel switches. The switch address is generated by the
parallel data bus.
DIP
13
PLCC
15
Pin Name
IO_REQUEST/
Description
Parallel handshake input signal
This signal is driven low when a parallel command is issued to the
CY545. It is used as part of the parallel command handshake. If the
parallel command function is not used, this signal may select a fixed
serial baud rate as follows:
0 = 300 baud, 1 = 2400 baud, F = 9600 baud
DIP
14
PLCC
16
Pin Name
(I/O) XMEM_SEL/
Description
External local memory select
This signal goes low when the CY545 reads or writes to the local external
memory. Data and addresses are generated by the parallel data bus. Up
to 64K bytes of external memory are supported. When this signal is
driven low at power-up or reset, the CY545 will not test for the Auto Start
key sequence or automatically execute commands from the external
memory.
DIP
15
PLCC
17
Pin Name
(I/O) BUSY/
Description
Parallel handshake acknowledgement
BUSY/ is used with IO_REQUEST/ to implement the two line parallel
command handshake. This signal indicates that the CY545 has accepted
a parallel data character from the device driving the IO_REQUEST signal.
If the parallel handshake is not used, this pin may be tied low to select
fixed baud rates through the IO_REQUEST signal.
© 2002 Cybernetic Micro Systems
8
Chapter 2 - Pinout & Package Overview
ETC [ ETC ]
