HSP Modems
Cirrus, Ambient, PCTEL (HSP), ESS & Motorola Modem Chipsets
The vast majority of modems come with either 3Com/TI, Lucent, or Rockwell/Conexant chipsets. There are a few others including the ESS, PCTel, and Cirrus/Ambient chipsets. I do not recommend the purchase of a modem with these chipsets. Most of the modems made with these chipsets are soft or win-modems - of the worst kind lacking a DSP (digital signal processor) - that place a high load on your PC's CPU.
As with any 56k modem, assuming you have a 56k-compatible line, the firmware for your modem is the single most important factor in the quality of your connection. While Cirrus/Ambient, PC-Tel, & ESS- based modems will get 56k connects under some conditions, there are more interoperability problems with these modems - and you should check to see if new firmware is available for your modem.
PCTel, Cirrus/Ambient, and ESSTech make chipsets - they don't make modems; the vendor that made the modem is responsible for support and firmware updates even though Cirrus and PCTel must develop the firmware. Note that Ambient Technologies is a spin-off of Cirrus Logic created to handle just the modem portion of Cirrus' business.
Here is a link that may help:
Hi-Val Modem Driver page - This company has made modems with Lucent, Rockwell, PCTel, ESS, and TI chipsets and has drivers (usually without version #) for them all.
Courtesy of 56k=v.Unreliable
We do not recommend the use of Software Modems!
Make certain you are using the appropriate firmware revision with
the Controllerless Modem.
