Guildline 6530 Series, Руководство оператора

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Section 5
OM6530-C1-00
19 November, 2019
5-4
Table 5-2 : IEEE-488 Pin Designations
5.2.7. IEEE-488 INPUT BUFFERING
The IEEE-488 input buffer is 256 bytes long. The input full bit is set when the buffer is
above 75% full (64 bytes remaining), hence if the programmer limits messages sent to the
6530 to 32 bytes and checks the IFL bit in the status register before sending each
message, then under normal operating conditions the buffer should never overflow. If the
buffer is full and the programmer sends more data, the 6530 will perform the necessary
handshaking as per usual, but the data will be lost, this is done for two reasons:
If the buffer is full, the fault must have originated with the controller, since the 6530
interprets most commands in fewer than 15 milliseconds. This prevents the 6530 from
locking up the IEEE-488 bus.
5.2.8. IEEE-488 OUTPUT BUFFERING
Output from query commands are placed into a 256 byte output buffer. When the
controller reads data from the 6530 the responses will come from the output buffer in,
first-in first-out order. If for some reason the controller does not read the responses from
its query commands the output buffer will overflow, in this case the first data into the
buffer will still be valid and the later data will be lost. When output data is lost the query
Pin Name Description
1 DIO1 Data Input Output Line 1
2 DIO2 Data Input Output Line 2
3 DIO3 Data Input Output Line 3
4 DIO4 Data Input Output Line 4
5 EIO End or Identify
6 DAV Data Valid
7 NRFD Not Ready for Data
8 NDAC Not Data Accepted
9 IFC Interface Clear
10 SRQ Service Request
11 ATN Attention
12 SHIELD Screening on Cable (connected to safety ground)
13 DIO5 Data Input Output Line 5
14 DI06 Data Input Output Line 6
15 DIO7 Data Input Output Line 7
16 DIO8 Data Input Output Line 8
17 REN Remote Enable
18 GND6 Ground wire of twisted pair with DAV
19 GND7 Ground wire of twisted pair with NRFD
20 GND8 Ground wire of twisted pair with NDAC
21 GND9 Ground wire of twisted pair with IFC
22 GND10 Ground wire of twisted pair with SRQ
23 GND11 Ground wire of twisted pair with ATN
24 GND Logic Ground