TMP92CM22 2007-02-16 92CM22-89(6) Connecting external memory
Figure 3.6.1 shows an example of how to connect external memory to the
TMP92CM22.
This example connects ROM and SRAM in 16-bit width.
Figure 3.6.1 Example of External Memory
By resetting, TMP92CM22 function as output port. Output latch of P82 (CS2)
is cleared to “0”, and output “L”. Output latch of P80 (CS0 ), P81 (CS1 ) and P83
(CS3) are set to “1”, and output “H”.
When set port 8 from por t function to CS functi on, set need bit of P8FC register
to “1”.
Note: When set P82 as CS2 after release reset, set function register remain output
latch of P82 is “0” (P8<P82> = 0). (P8FC<P82F> = 1)
If set function register (P8FC<P82F> = 1) after set output latch of P82 to “1”
(P8<P82> = 1), maybe don’t read ROM data during changing from port
function to CS2.
TMP92CM22 16-bit SRAM
RD
WRLL
WRLU
R/W
OE
LB
UB
R/W
CS0 CE
A
0
A
1
A
2
A1
A2
A3
A0 Not connetion
16-bit ROM
OE
CE
DQ [15:0]
A
0
A
1
A
2
CS2
D [15:0] I/O [16:1]