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 15 JTAG 19 8 Mbps interleaved PCM bus operation 20 3.3V operation with 5V tolerant I/O (for DS21352) 23 3. Changes in Register Definitions 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. 3.1.1 HDLC DS0 Control (section 15) Register Address Description RDC1 90h Receive HDLC DS0 Control Register 1 RDC2 91h Receive HDLC DS0 Control Register 2 TDC1 92h Transmit HDLC DS0 Control Register 1 TDC2 93h Transmit HDLC DS0 Control Register 2 3.1.2 Interleaved PCM Bus Operation (section 20) Register Address Description IBO 94h Interleave Bus Operation 3.2 Bit Assignment Changes within Existing Registers Highlights bit locations in the DS21352/DS21552 which have changed from the DS2152. Register Bit # DS2152 Symbol DS2152 Description DS21352/DS21552 Symbol DS21352/DS21552 Description CCR3 7 ESMDM Elastic Store Minimum Delay Mode RESMDM Rx Elastic Store Minimum Delay Mode CCR3 6 ESR Elastic Store Reset TCLKSRC Tx Clock Source Select CCR3 0 N/A Not assigned TESMDM Tx Elastic Store Minimum Delay Mode CCR6 6 N/A Not assigned RESALGN Rx Elastic Store Align CCR6 5 N/A Not assigned TESALGN Tx Elastic Store Align CCR7 5 N/A Not assigned RESR Rx Elastic Store Reset CCR7 4 N/A Not assigned TESR Tx Elastic Store Reset 4. Changes in Device Pin Out 4.1 Package types The DS2152 and DS21352/DS21552 are both offered in a 100 pin 14 x 14 x 1.4mm LQFP. Values listed are for body dimensions. 4.2 Device Pin Differences 4.2.1 JTAG Pins Pin # DS21352/DS21552 DS2152 Description 2 JTMS NC IEEE 1149.1 Test Mode Select 4 JTCLK NC IEEE 1149.1 Test Clock Signal 5 JTRST NC IEEE 1149.1 Test Reset 7 JTDI NC IEEE 1149.1 Test Data Input 10 JTDO NC IEEE 1149.1 Test Data Output 4.2.2 Interleaved PCM Bus Pins Pin # DS21352/DS21552 DS2152 Description 36 CI NC Carry In 54 CO NC Carry Out 4.2.3 Framer Mode Select Pin Pin # DS21352/DS21552 DS2152 Description 76 FMS NC Framer Mode Select 関連製品   APP 360: Aug 10, 2001 DS21352 3.3V DS21352および5V DS21552 T1シングルチップトランシーバ フルデータシート (PDF, 1.1MB) 無料 サンプル DS2152 強化型T1シングルチップトランシーバ フルデータシート (PDF, 1.3MB) 無料 サンプル DS21552 3.3V DS21352および5V DS21552 T1シングルチップトランシーバ フルデータシート (PDF, 1.1MB) 無料 サンプル 自動アップデート お客様が関心のある分野でアプリケーションノートが新規に掲載された際に自動通知Eメールの受信を希望する場合は、EE-Mail™にご登録ください。 We Want Your Feedback! フィードバックをお寄せください。 内容に満足されましたか、あるいは満足されていませんか？もっと良いページにできると思いますか？あるいは、単なるコメントでも結構です。フィードバックをお待ちしています。—マキシムはお客様からいただく訂正、提案を元に改善していきます。 このページを評価し、フィードバックを送信する。   ダウンロード、PDFフォーマット(43kB)  AN360, AN 360, APP360, Appnote360, Appnote 360