EE 308 Spring 2005EE 308Homework 11Due April 11, 20051. The figures below show some things which might be on the HCS12 bus in normal expandedwide mode. For each figure, indicate if that combinations of signals can occur. If so, explainwhat the memory cycle does — read or write, 8-bit or 16-bit access, what data is read fromor written to, what memory address(es) are accessed. If the combination of signals cannotoccur, explain why not.0x1234AD15−0ER/WLSTRB0x4321AD15−0ER/WLSTRB0x2345 0x5432AD15−0ER/WLSTRB0x3456 0x6543AD15−0ER/WLSTRB0x4567 0x76541EE 308 Spring 20052. The following table shows some values in the HC12 memory:0 1 2 3 4 5 6 7 8 9 A B C D E F4080 01 3F C6 80 5B 86 C6 03 5B 8D C6 FF 5B 02 4C 80Show what will b e on the address/data bus and the control lines when the HC12 does thefollowing:(a) Writes a 0xAA to address 0x4080.EPort APort BR/WLSTRB(b) Writes a 0x55AA to the two bytes at addresses 0x4082 and 0x4083.EPort APort BR/WLSTRB(c) Reads a single byte from addresses 0x4089.EPort APort BR/WLSTRB3. Immediately upon coming out of reset, an HCS12 is operating in Normal Expanded Widemode. How did the HCS12 know it should run in this mode — i.e. what pins did it check,and what was the state of those pins?4. Immediately upon coming out of reset, an HCS12 is operating in Normal Single Chip m ode.How did the HCS12 know it should run in this mode — i.e. what pins did it check, and whatwas the state of those pins?5. Immediately upon coming out of reset, an HCS12 is operating in Normal Single Chip m ode.How can you switch the chip into Normal Expanded Wide mode? Write some code to dothis.2EE 308 Spring 20056. You want to use an Altera 7064 chip to implement a general purpose I/O port at address0x4000. Write an Altera TDF file, or draw an Altera GDF file, which does the following:(a) Demultiplexes the address from the data. It generates the output lines A15-0. Theinputs are AD15-0 and the E clock.(b) Does the address decoding:• Generates an output W4000 which goes low when the HCS12 does a write to thebyte at memory address 0x4000.• Generates an output R4000 which goes low when the HCS12 does a read from thebyte at memory address 0x4000.• Generates an output W4001 which goes low when the HCS12 does a write to thebyte at memory address 0x4001.• Generates an output R4001 which goes low when the HCS12 does a read from thebyte at memory address 0x4001.The inputs to the device should be address lines A15-0, and the E, R/W, and
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