from the columns to the chip. e idea is that the scan lines cause ‘lows’ to be outputted on the
rows and the status of the columns are returned to the chip. Remember that this is the same
as the principle of keyboard interfacing discussed in Section 9.12, but here, the 8279 does this
automatically in response to the control words we use.
e return key code which is produced has a format as shown in Fig 10.17. is code is
stored in an eight-byte FIFO RAM where FIFO stands for ‘First-In First-Out’. is RAM
thus ...
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