AMD 32495b gxdb533 specupdate free download

File name 32495b_gxdb533_specupdate.pdf

AMD GeodeTM GX DB533 Development Board Specification Update Scope This document discusses known issues of the AMD Note: This is revision B of this document. The change GeodeTM GX DB533 development board. from revision A (dated September 2004) is the addition of issue #2. The table below provides a summary of the issues. A detailed description of each issue, its impact and a recom- mended resolution/fix follow. Issues Summary Issue #1 Description 1 LAN Connectivity LED does not light 2 IDE drives configured for Cable Select (CSEL) will not work (Rework B) 1. Issue numbers may not be sequential since issues are omitted once they are resolved. Issues 1 LAN Connectivity LED does not light 2) IDE drives configured for Cable Select (CSEL) will not work (Rework B) Description: The LAN connection LED (green LED on the LAN connector) will never illuminate. Per the Description: Overview of CSEL from the ATA speci- schematic, U15 is supposed to drive low if either of fication: IDE devices can be configured to use the its inputs are low. The inputs are from the LAN CSEL (Cable Select) pin to determine their assign- controller's MA1 and MA2 lines that go low for 10 ment. The host provides a low on this pin. The IDE Mb/s or 100 Mb/s respectively. By design, the green cable will leave the pin open on the Device 1 LED on the LAN connector is supposed to illuminate connector on a two-device cable. If a device sees a for either speed. The schematic logic symbol for U15 low on its CSEL pin, it will be Device 0, otherwise, a shows an AND gate, which would yield the desired high will cause it to become Device 1. results. However, the part called out on the sche- The host (in this case, the GX DB533) has left the pin matic is an OR gate. With the LAN controller driving floating. Devices will configure themselves as Device either MA1 low or MA2 low (never both), the output of 1. In a single-device configuration, the system will not this gate will never be low. find the boot device. In a two-device configuration, Implications: By not illuminating the connectivity they will both attempt to become Device 1 and will LED, a user