Merge pull request #35 from xmos/feature/refactor_i2c_gpio_setup

Rename vars and add comments
xmos · Nov 5, 2021 · e454db1 · e454db1
2 parents 3dc8d93 + b2ee3bb
commit e454db1
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Showing 2 changed files with 10 additions and 6 deletions.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # VocalFusion Raspberry Pi Setup Change Log
 
+## 4.3.1
+
+  * Fix comments and reg names in setup_dac.py
+
 ## 4.3.0
 
   * Added support for xvf3610 EVK board

diff --git a/resources/clk_dac_setup/setup_dac.py b/resources/clk_dac_setup/setup_dac.py
@@ -26,8 +26,7 @@ def setup_dac(args):
     if args.hw == "xvf3600" or args.hw == "xvf3610" :
 
         # I2C expander register addresses
-        I2C_EXPANDER_INPUT_PORT_REG = 0x01
-        I2C_EXPANDER_OUTPUT_PORT_REG = 0x02
+        I2C_EXPANDER_OUTPUT_PORT_REG = 0x01
         I2C_EXPANDER_CONFIGURATION_REG = 0x03
         I2C_EXPANDER_INTERRUPT_MASK_REG = 0x45
 
@@ -43,17 +42,18 @@ def setup_dac(args):
 
         # Set pin values
         # set DAC_RST_N to 0 and enable level shifters on the I2C expander
-        INPUT_PORT_MASK = (1<<XVF_RST_N_PIN) | \
+        OUTPUT_PORT_MASK= (1<<XVF_RST_N_PIN) | \
                           (1<<INT_N_PIN)     | \
                           (1<<BOOT_SEL_PIN)  | \
                           (1<<MCLK_OE_PIN)   | \
                           (1<<SPI_OE_PIN)    | \
                           (1<<I2S_OE_PIN)    | \
                           (1<<MUTE_PIN)
 
-        bus.write_byte_data(I2C_EXPANDER_ADDRESS, I2C_EXPANDER_INPUT_PORT_REG, INPUT_PORT_MASK)
+        bus.write_byte_data(I2C_EXPANDER_ADDRESS, I2C_EXPANDER_OUTPUT_PORT_REG, OUTPUT_PORT_MASK)
         time.sleep(0.1)
-        # Configure pin directions:
+        # Configure pin directions. Setting to 1 means input, or Hi-Z. So anything not mentioned
+        # below will be an output. Note reset, int and boot_sel NOT driven because they are set high in the mask
         # use DAC_RST_N and level shift OE as driven outputs
         # Configure the mute pin as input only for XVF3610
         if args.hw == "xvf3600":
@@ -76,7 +76,7 @@ def setup_dac(args):
             bus.write_byte_data(I2C_EXPANDER_ADDRESS, I2C_EXPANDER_INTERRUPT_MASK_REG, INTERRUPT_MASK)
 
         # Reset the DAC
-        bus.write_byte_data(I2C_EXPANDER_ADDRESS, I2C_EXPANDER_INPUT_PORT_REG, INPUT_PORT_MASK | (1<<DAC_RST_N_PIN))
+        bus.write_byte_data(I2C_EXPANDER_ADDRESS, I2C_EXPANDER_OUTPUT_PORT_REG, OUTPUT_PORT_MASK | (1<<DAC_RST_N_PIN))
         time.sleep(0.1)
 
     else: