RoboteQ AX2850 user manual Query Heatsink Temperatures, Query Battery Voltages, ?r or ?R, ?m or ?M

Controller Commands and Queries

values represent the actual speed measured by the tachometer. When used in position mode, the values represent the actual motor position measured by a potentiometer. In all other modes, the values represent the measured voltage (0 to 5V) applied to the analog inputs. The values are signed Hexadecimal numbers ranging from -127 to +127. The -127 value represents 0V at the input, the 0 value represents 2.5V, and the +127 value repre- sents +5V.

Analog 1 and 2
Syntax:	?p or ?P
Analog 3 and 4
Syntax:	?r or ?R
Reply:	nn
	mm

Where:nn = analog input 1 (or 3) value, speed or position

mm= analog input 2 (or 4) value, speed or position

Notes:

The command returns a signed hexadecimal number where 0 to +127 is represented by 00 to 7F, and -1 to -127 is represented by FF to 80 respectively.

On controllers prior to RevB, querying Analog inputs 3 and 4 will return a meaningless number.

Query Heatsink Temperatures

Description:

This query will cause the controller to return values based on the temperature measured by internal thermistors located at each heatsink side of the controller. Because NTC ther- mistors are non-linear devices, the conversion or the read value into a temperature value requires interpolation and a look up table. Figure 39 on page 69 shows this correlation.

Sample conversion software code is available from Roboteq upon request. The values are unsigned Hexadecimal numbers ranging from 0 to 255. The lowest read value represents the highest temperature.

Syntax: ?m or ?M

Reply:nn mm

Where:nn = thermistor 1 read value

mm= thermistor 2 read value

Notes:

The hexadecimal format is intended to be deciphered by a microcontroller. When exercis- ing the controller manually, you may use the Decimal to Hexadecimal conversion table on page 166.

Query Battery Voltages

Description:

This query will cause the controller to return values based on two internally measured volt- ages: the first is the Main Battery voltage present at the thick red and black wires. The sec- ond is the internal 12V supply needed for the controller’s microcomputer and MOSFET

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