Solartron Mobrey 3595 4C, User Manual

Page: 43 / 128

3595 4C User Manual Part One Programming the 3595 4C Interface card
35952350 (CH03/AA)
3-15
3.4.9 Reading the received data status
The Receive Table has the format shown in Figure 3.6. Four consecutive bytes are assigned to each IMP,
and these contain the receive status for data streams 0 through 3. For each IMP and data stream, the table
tells the Host PC whether the data transmitted by the IMP is ready in the ‘on-card’ RAM, or whether the
card has failed to receive this data. Each receive status byte also contains an address offset, which tells
the Host PC where to start reading the data stream on the relevant page of RAM.
0x01
0x02
0x03
0x04
0x05
0x06
0x00 DR RXE
Bit 7 Bit 0
Receive
Table
IMP 1
0xC4
0xC5
0xC6
0xC7
0x07
ADDRESS OFFSET
Data Stream 0
Data Stream 1
Data Stream 2
Data Stream 3
Data Stream 0
Data Stream 1
Data Stream 2
Data Stream 3
Data Stream 0
Data Stream 1
Data Stream 2
Data Stream 3
IMP 2
IMP 50
Figure 3.6: Receive Table
For each receive status byte, the bit functions are:
DR Data Ready. When set, this bit indicates that some new data has been received
and is ready on the RAM page assigned to storing IMP measurement results.
RXE Receive Data Error. When set, this bit indicates that the 4C Interface card has
failed after three attempts to receive data transmitted by an IMP.
Address Offset Bits 0 through 5 contain a RAM location offset (divided by 4). This points to the
location in RAM where the first byte of the data stream is located. All data starts
on long word boundaries (four bytes).
(The measurement results received from IMP 1 through IMP 50 are stored on
RAM pages 2 through 51.)