I'm using forscan 2.2.7 with a 98 Mazda 626 GF 2L and a scantool.net Elmscan5 adaptor using J1850 PWM protocol, iirc.
I've noticed that whether I monitor 6 pid's or just one, I only get data samples approximately every 75ms.
I'm pretty sure the adaptor is capable of a faster polling interval than that, but I'm not sure how to change it.
How to get more frequent data samples
Re: How to get more frequent data samples
1. Try to improve interface performance in FORScan. We just added new article about it:
http://forscan.org/forum/viewtopic.php?f=4&t=1763
AFAIK Elmscan5 has FTDI chip inside so you should be able to reach good improvement this way.
2. There is special "block" mode reading data that really much faster. It is not supported in FORScan v2 yet but was supported in FORScan v1 (for J1850 PWM only). You may try to download v1.3.9 (at the bottom of Download page). If it works at all (it is very old so may have compatibility issues), it should show much better performance. We are going to add the blocking mode in v2 too, but to be honest very few users need it so it is not top priority yet.
http://forscan.org/forum/viewtopic.php?f=4&t=1763
AFAIK Elmscan5 has FTDI chip inside so you should be able to reach good improvement this way.
2. There is special "block" mode reading data that really much faster. It is not supported in FORScan v2 yet but was supported in FORScan v1 (for J1850 PWM only). You may try to download v1.3.9 (at the bottom of Download page). If it works at all (it is very old so may have compatibility issues), it should show much better performance. We are going to add the blocking mode in v2 too, but to be honest very few users need it so it is not top priority yet.
Re: How to get more frequent data samples
Found a very good writeup on how to set FTDI latency in a variety of operating systems:
https://projectgus.com/2011/10/notes-on ... h-arduino/
https://projectgus.com/2011/10/notes-on ... h-arduino/