November 2014
Beginner to intermediate
248 pages
4h 40m
English
Content preview from Raspberry Pi Hardware Reference
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
Start your free trial
CHAPTER 9
UART
The Raspberry Pi has a UART interface to allow it to perform serial data communications. The data lines used are 3.3 V logic-level signals and should not be connected to TTL logic (+5 V) (they also are not RS-232 compatible). To communicate with equipment using RS-232, you will need a converter module.
RS-232 Converter
While an industrious person could build their own RS-232 converter, there is little need to do so when cheap converters are available.
Figure 9-1 shows a MAX232CSE chip interface that I use. (This unit supports only the RX and TX lines.) When searching for a unit, be sure that you get one that works with 3 V logic ...