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package ChiselTests
import Chisel._
class Risc extends Module {
val io = new Bundle {
val isWr = Bool(INPUT)
val wrAddr = UInt(INPUT, 8)
val wrData = Bits(INPUT, 32)
val boot = Bool(INPUT)
val valid = Bool(OUTPUT)
val out = Bits(OUTPUT, 32)
}
val file = Mem(Bits(width = 32), 256)
val code = Mem(Bits(width = 32), 256)
val pc = Reg(init=UInt(0, 8))
val add_op :: imm_op :: Nil = Enum(Bits(width = 8), 2)
val inst = code(pc)
val op = inst(31,24)
val rci = inst(23,16)
val rai = inst(15, 8)
val rbi = inst( 7, 0)
val ra = Mux(rai === Bits(0), Bits(0), file(rai))
val rb = Mux(rbi === Bits(0), Bits(0), file(rbi))
val rc = Wire(Bits(width = 32))
io.valid := Bool(false)
io.out := Bits(0)
rc := Bits(0)
when (io.isWr) {
code(io.wrAddr) := io.wrData
} .elsewhen (io.boot) {
pc := UInt(0)
} .otherwise {
switch(op) {
is(add_op) { rc := ra +% rb }
is(imm_op) { rc := (rai << 8) | rbi }
}
io.out := rc
when (rci === UInt(255)) {
io.valid := Bool(true)
} .otherwise {
file(rci) := rc
}
pc := pc +% UInt(1)
}
}
class RiscTester(c: Risc) extends Tester(c) {
def wr(addr: BigInt, data: BigInt) = {
poke(c.io.isWr, 1)
poke(c.io.wrAddr, addr)
poke(c.io.wrData, data)
step(1)
}
def boot() = {
poke(c.io.isWr, 0)
poke(c.io.boot, 1)
step(1)
}
def tick(isBoot: Boolean) = {
if (isBoot)
poke(c.io.boot, 0)
step(1)
}
def I (op: UInt, rc: Int, ra: Int, rb: Int) = {
// val cr = Cat(op, UInt(rc, 8), UInt(ra, 8), UInt(rb, 8)).litValue()
val cr = op.litValue() << 24 | rc << 16 | ra << 8 | rb
println("I = " + cr)
cr
}
val app = Array(I(c.imm_op, 1, 0, 1), // r1 <- 1
I(c.add_op, 1, 1, 1), // r1 <- r1 + r1
I(c.add_op, 1, 1, 1), // r1 <- r1 + r1
I(c.add_op, 255, 1, 0)) // rh <- r1
wr(0, 0) // skip reset
for (addr <- 0 until app.length)
wr(addr, app(addr))
def dump(k: Int) {
println("K = " + k)
peek(c.ra)
peek(c.rb)
peek(c.rc)
peek(c.io.out)
peek(c.pc)
peek(c.inst)
peek(c.op)
peek(c.rci)
peek(c.rai)
peek(c.rbi)
peekAt(c.file, 1)
}
boot()
dump(0)
var k = 0
do {
tick(k == 0); k += 1
dump(k)
} while (!(peek(c.io.valid) == 1 || k > 10))
expect(k <= 10, "TIME LIMIT")
expect(c.io.out, 4)
}
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