
Preliminary
9
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MSX340
Introduction (Continued)
TABLE 3. RapidConfigure Input
Read and Reset Commands
When RCI[1:0] are equal to 11 a Read or Reset command is executed (see Table 4: Reset Commands).
Reset Commands
TABLE 4. Reset Commands (Continued)
RCC[0], RCB[9:0], and RCA[9:0] have no function during a reset command and must be written as zeroes.
Crosspoint Read Commands
A crosspoint read is used to check whether two ports are
connected through the crosspoint array. The two ports are
addressed using RCA[9:0] and RCB[9:0]
The MSX device uses RCC[0] to show whether the two
ports are connected. It drives RCC[0] HIGH if the two ports
are connected, and pulls RCC[0] low if the two ports are
not connected.
I/O Buffer Read Commands
I/O Buffer Reads are more complicated (see Table 5: I/O
Buffer read Commands). The port to be read is addressed
using RCA[9:0]. The MSX340 uses RCA[9:0] and RCB[9:0]
to return all of the configuration data for the particular I/O
buffer.
RCI [1:0]
Description
00
Force Testing Command. Force commands can force a port to drive either a one or a zero to either the pad or
crosspoint array. These commands are generally only used for diagnostic testing.
01
I/O Buffer Programming Command. These commands are used to configure a port as an input or output,
registered or not, etc.
10
Crosspoint Array Programming Command. Crosspoint connections can be made or broken, or an individual port
can be reset.
11
Read and Reset Commands. This setting is used to read back configuration data from an I/O buffer or crosspoint
connection information. It can also be used to reset all of the I/O buffers and the crosspoint array.
RCC [2:1]
Description
00
Reserved. This is not a valid command.
01
Reserved. This is not a valid command.
10
Crosspoint Array Reset. This command will reset the entire crosspoint array, breaking any previously existing
connections.
11
Crosspoint Array and I/O Buffer Reset. This command resets both the I/O buffers and the crosspoint array as
described above.
1
0
1
0
RCI[1:0]
RCC[3:0]
RCB[9:0]
RCA[9:0]
Reset Cmd Options
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
0
1
Reset Command
Read/Reset Cmd
0
1
0
RCI[1:0]
RCC[3:0]
RCB[9:0]
RCA[9:0]
Cross Point Read
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
0
1
Read Command
Read/Reset Cmd
0
Port #1
Port #2
1
0
RCI[1:0]
RCC[3:0]
RCB[9:0]
RCA[9:0]
I/O Buffer Config Read
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
0
1
Read Command
Read/Reset Command
0
I/O Buffer Address
0