Xylem H-264 - Manual (Page 14)

ASI v2 Operations (PRELIMINARY)
where N is the decimal count and V is battery voltage. The transmitter cutoff threshold is a
count of 2005, at 9.00 volts.
Put High Speed Xtal MCLK on P16 & Xtal2 on ACLK
This diagnostic is used to measure the accuracy of the precision crystal time base, and the
current consumption during high speed processing. The 6.500 MHz crystal is started, selected
as the processor clock and output on “MCLK” (P16). This is the time base used for the FSK
tone generation and high speed processing during transmission and therefore is required to be
precise. The measured frequency at room temperature should be between 6.500325 MHz and
6.499675 MHz (or +/- 50 ppm). Additionally, the 32.768 kHz crystal clock is output to test point
“ACLK” (P17, or J3 pin 2). This is used for baud rate timing, the transmitter “watch dog timer”,
the transmitter duty cycle timer and the Field Test Tool transmission timer. At room
temperature “ACLK” should measure between 32,767.34 Hz and 32,768.66 Hz (or +/- 20 ppm).
Put DCO MCLK on P16
This diagnostic is used to measure the RC DCO frequency and current during low speed
processing (“Buffer Conversion Processing’). The basic MSP430 RC DCO clock is output on
“MCLK” (P16). As described in the SWDelayS and SWDelayL diagnostic routines above, this
oscillator specification is very wide. The nominal frequency is 780 kHz (at 3.3 V), but can range
between 624 kHz and 934 kHz (+/- 20%).