Changes between Version 120 and Version 121 of gsc

Timestamp:

04/29/2025 05:04:13 PM (6 days ago)

Author:

Ryan Erbstoesser

Comment:

add notes for sample rate

gsc

@@ -358 +358 @@
 
 [=#hwmon]
-== System Temperature and Voltage Monitor ==
-The GSC implements system voltage and temperature monitoring (similar to industry standard AD7418) at i2c slave address {{{0x29}}}. For each analog to digital converter (ADC) input, the value can be read at a register offset. The register mapping differs depending on the version of the GSC:
+== System Temperature and Voltage Monitor and Analog Input==
+The GSC implements system voltage and temperature monitoring (similar to industry standard AD7418) at i2c slave address {{{0x29}}}. For each analog to digital converter (ADC) input (12-bit), the value can be read at a register offset. The register mapping differs depending on the version of the GSC:
 
 [=#hwmon_v3]
@@ -365 +365 @@
 The following 16-bit registers (MSB first, LSB second) are available:
 
-system monitor registers:
+System monitor registers:
 ||= Name =||= Register =||= Note =||
 || Board Temp =||= 0x06 =||= Deg C/10 ||
@@ -396 +396 @@
  1. See [#fan fan] below
  2. Consult individual board hardware manual or the Linux device-tree for a description of what voltage rail this is and what voltage divider is applied in order to scale it. Once scaled you can use {{{<scaled adc value> * 2500 / 4096}}} (2.5V ref/12 bit ADC) to calculate your ADC reading in mV. The Newport Linux kernel and BDK use information from the Linux Device-tree to scale and name these ADC's. 
+  1. Venice commonly uses a 0-5V input on the ADC1 and ADC2 lines. This has a 10k voltage divider resistor to bring it to 2.5V to the GSC. 
+  1. The sampling rate for ADC1 can vary. To calculate the maximum sample rate, there are a lot of variables, but it will be over 1Hz. Reference the MSP430FR5847 documentation from TI. 
  3. Vin (Board Input voltage) is evaluated at the board's primary power supply input and offset by an estimated diode drop and thus may differ from your actual power supply within a volt or so.
+
+
 
 A Linux 'Hardware Monitor' ({{{hwmon}}}) driver is available  which provides simple standard access to the above temperature/voltage registers via sysfs. The arguments have been given labels which define the source. The user can “cat” the label to determine the source. The hwmon will be found in /sys/class/hwmon/hwmonx where x is a number. Check all hwmonx directories, starting with x=0 and then x=1 until identifying the correct hwmon where the values are contained. 
@@ -477 +481 @@
 The following table shows the set of registers supported (Note each board supports a subset of these - an unsupported {source} will return a full-scale reading of 16,777,215)
 
-system monitor registers:
+System monitor registers:
 ||= Name =||= Register =||= Parameter =||= Units =||= Description =||
 || temp1       || 0x00           || Temperature   || Deg C/10    || SBC Temperature   ||