TX Fast Counters
Verfasst: 30 Nov 2010, 23:11
Hi,
I took a look at what the TX counters are capable of doing in terms of frequency and pulse width, as I had trouble making them work at anything close to the specified 1kHz. In short this is what I found:
- The fast counters can realistically only handle about 500Hz with a reasonable duty cycle tolerance of 20-60%.
- The fast counters can in theory operate at the specified 1000Hz but only with a very specific narrow duty cycle range of approximately 20-30%, which is a fairly a-typical cycle for pulse generating sensors.
- The counters are just fast enough to handle the pulses from the FischerTechnik encoder motors, which provides pulses at about 430Hz at 9V, or 360Hz when driven through the TX controller. The encoder pulses have a 45% duty cycle.
- The measured specification of the TX Controller’s fast counters is:
- Minimum ‘high’ pulse duration: 0.23ms
- Minimum ‘low’ pulse duration: 0.77ms
Full report is here: http://82.95.86.128/ftpub/TX_fast_counters.pdf
I'm curious to see if new firmware could bring improvements, assuming these limitations are at least partly imposed by the firmware.
Willem Evert Nijenhuis.
I took a look at what the TX counters are capable of doing in terms of frequency and pulse width, as I had trouble making them work at anything close to the specified 1kHz. In short this is what I found:
- The fast counters can realistically only handle about 500Hz with a reasonable duty cycle tolerance of 20-60%.
- The fast counters can in theory operate at the specified 1000Hz but only with a very specific narrow duty cycle range of approximately 20-30%, which is a fairly a-typical cycle for pulse generating sensors.
- The counters are just fast enough to handle the pulses from the FischerTechnik encoder motors, which provides pulses at about 430Hz at 9V, or 360Hz when driven through the TX controller. The encoder pulses have a 45% duty cycle.
- The measured specification of the TX Controller’s fast counters is:
- Minimum ‘high’ pulse duration: 0.23ms
- Minimum ‘low’ pulse duration: 0.77ms
Full report is here: http://82.95.86.128/ftpub/TX_fast_counters.pdf
I'm curious to see if new firmware could bring improvements, assuming these limitations are at least partly imposed by the firmware.
Willem Evert Nijenhuis.