DS21352/DS21552 versus DS2152 Single Chip Transceiver
Aug 10, 2001
Abstract: This application note will help with the migration from a current design using the DS2152 single chip transceiver (SCT) to one using the DS21352 or DS21552 SCT. These two devices are foot print compatible which allows the DS2152 to be replaced with only minor modifications to both the hardware and software. Some of the benefits of the migration to the DS21352 or DS21552 are that these devices have a more advanced HDLC, support JTAG test functions, multiple devices can communicate on a single high-speed bus, and operate at 3.3 volts with 5.0 volt tolerant I/O. To take advantage of these new functions, the application note outlines the specific hardware and software differences. It also indicates the specific sections of the DS21352 and DS21552 data sheet which have more information on the new functions what are available.
1. Introduction
This application note highlights the differences between the DS21352/DS21552 and the DS2152. The DS21352/DS21552 is a superset of the DS2152 maintaining a consistent pin out and register set. All of the original features of the DS2152 have been retained and software created for the DS2152 is transferable to the DS21352/DS21552 with minimal effort. The DS21352 and DS21552 are functionally equivalent with the only difference being the required supply voltage ?Ethe DS21352 operates at 3.3V and the DS21552 operates at 5V.
2. Additional Functionality
New Features
Data Sheet Section
HDLC controller
Buffer depth increased from 16 to 64 bytes HDLC over DS0 functionality added
When implementing the new features of the DS21352/DS21552, a priority was placed on preserving the DS2152’s register map to facilitate code migration from existing DS2152 designs. This section highlights register additions and differences found in the DS21352/DS21552.
3.1 New Feature Register Usage
Highlights specific registers related to new features. Each item can be found in the data sheet under the listed sections.
