implement tsens instruction, fixes #1

Author: ThomasWaldmann

demo.S

@@ -48,6 +48,8 @@ rel_f:      jumpr +1, 23, GE
 
             adc r0, 0, 1
 
+            tsens r0, 42
+
             nop
             wait 1000
             wake

esp32_ulp/opcodes.py

@@ -61,6 +61,8 @@
 SUB_OPCODE_END = 0
 SUB_OPCODE_SLEEP = 1
 
+OPCODE_TSENS = 10
+
 OPCODE_HALT = 11
 
 OPCODE_LD = 13
@@ -133,6 +135,14 @@ def make_ins(layout):
 """)
 
 
+_tsens = make_ins("""
+    dreg : 2        # Register where to store TSENS result
+    delay : 14      # Number of cycles needed to obtain a measurement
+    unused : 12     # Unused
+    opcode : 4      # Opcode (OPCODE_TSENS)
+""")
+
+
 _adc = make_ins("""
     dreg : 2        # Register where to store ADC result
     mux : 4         # Select SARADC pad (mux + 1)
@@ -400,6 +410,14 @@ def i_wait(cycles):
     return _delay.all
 
 
+def i_tsens(reg_dest, delay):
+    _tsens.dreg = get_reg(reg_dest)
+    _tsens.delay = get_imm(delay)
+    _tsens.unused = 0
+    _tsens.opcode = OPCODE_TSENS
+    return _tsens.all
+
+
 def i_adc(reg_dest, adc_idx, mux):
     _adc.dreg = get_reg(reg_dest)
     _adc.mux = get_imm(mux)

tests/compat/io.S

@@ -7,3 +7,6 @@
             i2c_wr 0x23, 0x42, 7, 0, 1
 
             adc r0, 1, 2
+
+            tsens r0, 42
+