safer use of GPIO during POST

src/ttboard/boot/post.py

@@ -12,7 +12,7 @@
 from ttboard.pins.upython import Pin
 import ttboard.util.time as time
 from ttboard.boot.first import FirstBoot
-from ttboard.pins.gpio_map import GPIOMap
+import ttboard.pins.gpio_map as gp
 from ttboard.demoboard import DemoBoard
 from ttboard.mode import RPMode
 
@@ -37,7 +37,7 @@ def read_all_pins(self) -> dict:
             to read value.
         '''
         pin_states = dict()
-        for name, io in GPIOMap.all().items():
+        for name, io in gp.GPIOMap.all().items():
             p = Pin(io, Pin.IN)
             pin_states[name] = p() 
 
@@ -54,14 +54,14 @@ def read_pin(cls, pin:str) -> int:
             @return: the value read
         '''
 
-        p = GPIOMap.get_raw_pin(pin, Pin.IN)
+        p = gp.GPIOMap.get_raw_pin(pin, Pin.IN)
         if p is None:
             raise KeyError(f'No pin named {pin} found')
         return p()
 
     @classmethod 
     def write_pin(cls, pin:str, value:int):
-        p = GPIOMap.get_raw_pin(pin, Pin.OUT)
+        p = gp.GPIOMap.get_raw_pin(pin, Pin.OUT)
         if p is None:
             raise KeyError(f'No pin named {pin} found')
         p(value)
@@ -70,17 +70,15 @@ def write_pin(cls, pin:str, value:int):
 
     @classmethod 
     def dotest_buttons_held(cls):
-        mux_selectpin = GPIOMap.get_raw_pin('hk_csb', Pin.OUT)
+        mux_selectpin = gp.GPIOMap.get_raw_pin('hk_csb', Pin.OUT)
         if mux_selectpin is not None:
             mux_selectpin(1) # have mux, make sure it's is pointed right way
-        if cls.read_pin(GPIOMap.project_clock()) and not cls.read_pin(GPIOMap.project_reset()):
+        if cls.read_pin(gp.GPIOMap.project_clock()) and not cls.read_pin(gp.GPIOMap.project_reset()):
             log.info('POST "do test" buttons held')
             return True 
 
         return False
 
-# could also check
-
     @classmethod 
     def first_boot(cls):
         return FirstBoot.is_first_boot()

src/ttboard/pins/pins.py

@@ -197,12 +197,14 @@ def output_pins(self):
 
     @property 
     def output_byte(self):
+
         if platform.IsRP2040:
             return platform.read_output_byte()
         return self._read_byte(self.outputs)
 
     @output_byte.setter 
     def output_byte(self, val:int):
+
         if platform.IsRP2040:
             platform.write_output_byte(val)
         else:
@@ -227,6 +229,7 @@ def input_pins(self):
 
     @property 
     def input_byte(self):
+
         if platform.IsRP2040:
             return platform.read_input_byte()
 
@@ -235,6 +238,7 @@ def input_byte(self):
 
     @input_byte.setter 
     def input_byte(self, val:int):
+
         if platform.IsRP2040:
             platform.write_input_byte(val)
         else:
@@ -261,6 +265,8 @@ def bidir_pins(self):
 
     @property 
     def bidir_byte(self):
+
+
         if platform.IsRP2040:
             return platform.read_bidir_byte()
 

src/ttboard/util/platform.py

@@ -4,6 +4,8 @@
 @author: Pat Deegan
 @copyright: Copyright (C) 2024 Pat Deegan, https://psychogenic.com
 '''
+
+
 RP2040SystemClockDefaultHz = 125000000
 
 IsRP2040 = False 
@@ -14,8 +16,6 @@
     pass
 
 
-
-
 if IsRP2040:
     '''
         low-level machine related methods.
@@ -34,7 +34,8 @@
         into an output.
         
         NOTE: [muxing] there is a MUX on some pins of the low 
-        output nibble, that could in theory interfere with this.
+        output nibble on TT04/05 demoboards, that could in theory
+        interfere with this.
         If you use the tt.shuttle to select/enable projects, it 
         ensures that the mux is set to let these pins out as you'd 
         expect.  If you're down in the weeds and want to make sure 
@@ -65,6 +66,7 @@ def write_input_byte(val):
         # low nibble starts at 9 | high nibble at 17 (-4 'cause high nibble)
         val = ((val & 0xF) << 9) | ((val & 0xF0) << 17-4)
         # xor with current GPIO values, and mask to keep only input bits
+        # 0x1E1E00 == 0b111100001111000000000 so GPIO 9-12 and 17-20
         val = (machine.mem32[0xd0000010] ^ val) & 0x1E1E00
         # val is now be all the input bits that have CHANGED:
         # writing to 0xd000001c will flip any GPIO where a 1 is found
@@ -99,10 +101,8 @@ def read_bidir_byte():
     def write_output_byte(val):
         # low level machine stuff
         # move the value bits to GPIO spots
-        # for bidir, all uio bits are in a line starting 
-        # at GPIO 21
+
         val = ((val & 0xF) << 5) | ((val & 0xF0) << 13-4)
-        # xor with current GPIO values, and mask to keep only input bits
         val = (machine.mem32[0xd0000010] ^ val) & 0x1E1E0
         # val is now be all the bits that have CHANGED:
         # writing to 0xd000001c will flip any GPIO where a 1 is found,
@@ -111,6 +111,21 @@ def write_output_byte(val):
 
     @micropython.native
     def read_output_byte():
+
+        # sample code to deal with differences between 
+        # PCBs, not actually required as we didn't move anything
+        # after all!
+        # global PCBVERSION_TT06
+        # all_io = machine.mem32[0xd0000004]
+        #if PCBVERSION_TT06 is None:
+        #    import ttboard.boot.demoboard_detect as dbdet
+        #    PCBVERSION_TT06 = True if dbdet.DemoboardDetect.PCB == dbdet.DemoboardVersion.TT06 else False
+
+        #if PCBVERSION_TT06:
+        #    # gpio output bits are
+        #    # 0x1e1e0 == 0b11110000111100000 so GPIO5-8 and GPIO 13-17
+        #    val =  ((all_io & (0xf << 13)) >> (13 - 4)) | ((all_io & (0xf << 5)) >> 5)
+        #else:
         # just read the high and low nibbles from GPIO and combine into a byte
         return ( (machine.mem32[0xd0000004] & (0xf << 13)) >> (13-4)) | ((machine.mem32[0xd0000004] & (0xf << 5)) >> 5)