# Samples and known issues

Source: [https://docs.qualcomm.com/doc/80-WL748-1/topic/samples-and-known-issues.html](https://docs.qualcomm.com/doc/80-WL748-1/topic/samples-and-known-issues.html)

## Sample testing

Source: [https://docs.qualcomm.com/doc/80-WL748-1/topic/samples-and-known-issues.html](https://docs.qualcomm.com/doc/80-WL748-1/topic/samples-and-known-issues.html)

### Engineering samples (ES)

Source: [https://docs.qualcomm.com/doc/80-WL748-1/topic/samples-and-known-issues.html](https://docs.qualcomm.com/doc/80-WL748-1/topic/samples-and-known-issues.html)

These devices undergo limited testing and sometimes have significant feature limitations.
            They are suitable to assist with PCB development, to conduct board-level electrical
            evaluation tests, and to explore manufacturing considerations. Engineering samples
            should not be used for product-level qualification.

### Commercial samples (CS)

Source: [https://docs.qualcomm.com/doc/80-WL748-1/topic/samples-and-known-issues.html](https://docs.qualcomm.com/doc/80-WL748-1/topic/samples-and-known-issues.html)

These devices undergo full production-level testing, and meet the specifications and
            features described in the device specification, except as otherwise noted in this
            document. They have passed device-level qualification. Commercial samples are suitable
            for performance testing, and also for product-level production and qualification.

## Known issues

Source: [https://docs.qualcomm.com/doc/80-WL748-1/topic/samples-and-known-issues.html](https://docs.qualcomm.com/doc/80-WL748-1/topic/samples-and-known-issues.html)

### Summary of known issues

Source: [https://docs.qualcomm.com/doc/80-WL748-1/topic/samples-and-known-issues.html](https://docs.qualcomm.com/doc/80-WL748-1/topic/samples-and-known-issues.html)

All known issues for each revision of the QCC748 device are summarized
            in [Table : Known issues – all sample types and revisions](https://docs.qualcomm.com/doc/80-WL748-1/topic/samples-and-known-issues.html#summary-of-known-issues__table_rbx_gq1_p1c). The text within the Issue column provides links
            to the sections of this document that explain the issues, regardless of the sample type
            (or types) on which they occur. An X in one or more of the sample type columns indicates
            that the issue occurs in the corresponding sample type.

The following information is provided for each issue:

- Issue description
- Impact to system performance
- Possible workarounds to minimize impact

Table : Known issues – all sample types and revisions

| Issue # | Issue description | Workaround | QCC748-2 CS (PRR=201)<br><br>QCC748-3 CS (PRR=301) |
| --- | --- | --- | :---: |
| Issue 1 | DMA accesses to the XIP address space across a 32‑byte boundary<br>                            result in a read data error. | Software workaround | X |
| Issue 2 | E907 hangs if prefetch data from an uninitialized PSRAM | Default software | X |

### Issues – description, impact, and workaround

Source: [https://docs.qualcomm.com/doc/80-WL748-1/topic/samples-and-known-issues.html](https://docs.qualcomm.com/doc/80-WL748-1/topic/samples-and-known-issues.html)

### Issue 1

| Description | DMA accesses to the XIP address space across a 32‑byte boundary<br>                                result in a read data error. |
| --- | --- |
| Impact | Result data error |
| Workaround | Software workaround:<br><ul class="ul" id="issues-description-impact-and-workaround__ul_v3p_rq1_p1c"><br>                                    <li class="li">User must ensure 32‑byte alignment when DMA accesses the XIP<br>                                        address.</li><br><br>                                    <li class="li">DMA INCx set to INC1 (INCx, x indicates the number of<br>                                        transfers).</li><br><br>                                </ul> |

### Issue 2

| Description | E907 hangs if prefetch data from an uninitialized pSRAM |
| --- | --- |
| Impact | System hang |
| Workaround | Default software:<br><ul class="ul" id="issues-description-impact-and-workaround__ul_acm_wq1_p1c"><br>                                    <li class="li">Use pmp/TZ to protect pSRAM addresses early in the chip's<br>                                        boot process.</li><br><br>                                    <li class="li">If pSRAM is initialized after system startup, it will<br>                                        unprotect this address segment.</li><br><br>                                </ul> |

Last Published: Apr 22, 2026

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