void act() {
// get aware of what capacity the memory features
memsize = memory->size();
cout << "CPU: size request served, capacity is " << memsize << " data units." << endl;
// make room for local computations
const unsigned char opbufsize = 10; // set this > 2!
char *operate_buf = new char[opbufsize];
// initialize operate_buf with some readable (ascii) data
for (char *x = operate_buf; x < operate_buf + opbufsize; x++) {
*x = 48 + (random() % 43); // some in the ascii alphanum domain (circa)
}
// A unit operation -- store operate_buf[0] into memory at some random address
// choose a random address (within memory space) to operate, warn, then write
address_t operaddr = random() % memsize;
cout << "CPU: will write " << operate_buf[0] << " into memory's " << operaddr << " cell." << endl;
// write and read ops might cause errors...
try {
memory->write(operate_buf[0], operaddr);
} catch (std::runtime_error &e) {
cout << "CPU: an error occurred: " << e.what() << endl;
return;
}
char tmpbuf;
try {
memory->read(tmpbuf, operaddr);
} catch (std::runtime_error &e) {
cout << "CPU: an error occurred: " << e.what() << endl;
return;
}
cout << "CPU: memory location " << operaddr << " now holding '" << tmpbuf << "'." << endl;
// A block operation -- store a bunch of data units into memory at some
// random address, then, fetch some of them back
operaddr = random() % (memsize - opbufsize);
// advicing data, and writing to memory
cout << "CPU: will write: "; for (unsigned char i = 0; i < opbufsize; i++) cout << operate_buf[i]; cout << endl;
try {
memory->writeblock(operate_buf, opbufsize, operaddr);
} catch (std::runtime_error &e) {
cout << "CPU: an error occurred: " << e.what() << endl;
return;
}
// reading back some piece of it
cout << "CPU: getting back " << opbufsize/2 << " units of data...";
char *newbuf = new char[opbufsize/2];
try {
memory->readblock(newbuf, opbufsize/2, operaddr);
} catch (std::runtime_error &e) {
cout << "CPU: an error occurred: " << e.what() << endl;
return;
}
cout << "CPU: got back ";
for (unsigned char i = 0; i < opbufsize/2; i++) cout << newbuf[i];
cout << endl;
delete[] operate_buf; // free the temporary buffer
}
void act() {
while (true) {
cout << "MemAdaptor: waiting for requests..." << endl;
// wait for a request to come
while (req.read() != true) wait();
// request now accepted
address_t memaddr = addr.read(); // read recipient address
// SIZE request?
if (memsize.read() == true) {
// SIZE request!
cout << "MemAdaptor: SIZE request income, processing...";
addr.write(memory->size());
cout << " done." << endl;
goto act_oper_ok;
}
// READ request?
if (r_w.read() == true) {
// READ request!
cout << "MemAdaptor: READ request income, processing...";
char val;
try {
memory->read(val, memaddr);
} catch (std::runtime_error &e) {
// an error occurred, reporting on the bus
goto act_oper_err;
}
data.write(val);
cout << " done." << endl;
goto act_oper_ok;
}
// in any other case..
// WRITE request!
cout << "MemAdaptor: WRITE request income, processing...";
try { memory->write(data.read(), memaddr); } catch (std::runtime_error &e) {
// an error occurred, reporting on the bus
goto act_oper_err;
}
cout << " done." << endl;
goto act_oper_ok;
act_oper_err: // an error happened operating the service
err.write(true);
while (req.read() != false) wait();
err.write(false);
continue;
act_oper_ok: // service went ok
ack.write(true); // request served
// wait for peer assertion
while (req.read() != false) wait();
ack.write(false); // terminate the operation
}
}