Meilhaus Electronic ME-1000 Series, Руководство пользователя

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Rev. 1.4E Manual ME-1000
Hardware Page 12 Meilhaus Electronic
3.3 Operation Modes
Depending on the version, the ME-1000 can have 64 or 128 I/O
lines. These are organised into 2 or 4 ports each 32 bits wide.
The 32 bit ports can be configured independently as input or out-
put by software. For input and output operation, use the ME-
1000 function library provided with the board. A port configured
as output can also be read in.
Note:
On power up, all ports are set automatically as input, therefore
all lines are in a high impedance state (see „Pull up/Pull down
Resistors” on page 13).
3.4 Switching of Input/Output Lines
The ports are divided as follows:
• Port A (PA0…PA31) and Port B (PB0…PB31) are available on
the base board´s D-Sub 78pin connector.
• Additionally for the ME-1000/128: Port C (PC0…PC31) and
Port D (PD0…PD31) are available on the ME-1001 extender
board´s D-Sub 78pin connector.
Make sure that all signals connected to the board are within the
TTL signal level specifications and that a connection to PC
ground (GND) exists.
On pins 19, 20, 38, 39, 58, 59, 77 and 78 a signal of +5 V from
the PC is available. The total load of these 8 pins should not ex-
ceed 500 mA. The pin configuration of the D-Sub 78pin connec-
tor can be found in Appendix „B Pinout“ on page 43.
Important note:
A port configured as output should never be switched by an
input signal!