Four Channel RS-422 / EIA-530 to TTL Converter The 422TTL and 422TTL33 convert RS-422 or EIA-530 signals to TTL at data rates up to 115.2 Kbps. Two channels are used to convert RS-422 to TTL and two channels are used to convert TTL to RS-422. Select the 422TTL for 5 VDC TTL or the 422TTL33 for 3.3 VDC TTL. A DB25 Male connector is used on the TTL side and a DB25 Female connector is used on the RS-422 / EIA-530 side. The converters support RD, TD, RTS, and CTS. Pin 7 is signal ground for both connectors. These units can work at baud rates up to 115.2 Kbps. Open pads are provided for each line. Therefore, if you choose to, you can change the pin connectors for any of the 4 channels. When converting a second RS-422 channel, use the corresponding RTS A and RTS B pins (refer to the diagram on the next page). These converters invert the TTL signal. Refer to the specifications table to determine polarity. An external +12 VDC power supply is required (not included).