HP Visualize J200 Reference Manual page 60

If the J Class Parallel Port DMA controller gets a parity error or bus timeout while mastering a
transaction, the transaction causing the error will be completed normally, but arbitration will be disabled
so no more DMA can be done. The Current Address register will point to the next address to be read after
the error. All of the data in the error transaction will be handshaked to the parallel device and the Current
Count register will have the value indicating the data just read had been processed; this should help in the
debug process.
RS–232 Registers
Table 4–3 shows suggested connector pinouts for the RS–232 interface. Both a nine position male D
connector, such as those used in PC products, and a twenty–five position female D connector, such as
those used in traditional workstations, are shown.
Signal
Table 4–3. RS–232 Connector Pinouts
Direction 9–Pin
Out 3
In 2
In 8
Out 7
In 1
In 6
In 9
Out 4
5
25–Pin Description
3 Transmit Data
2 Receive Data
5 Clear to send
4 Request to send
8 Data Carrier Detect
6 Data set ready
22 Ring Indicator
20 Data terminal ready
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