ERRATA SHEET
ST7SCR LIMITATIONS AND CORRECTIONS
18 SILICON IDENTIFICATION
This document refers only to ST7FSCR devices shown in Table 25. They are identifiable both
by the last letter of the Trace code marked on the device package and by the last 3 digits of
the Internal Sales Type printed on the box label (see also Figure 51)
Table 25. Device Identification
Trace Code marked on device
Flash Devices: “xxxxxxxxxX”
Internal Sales Type on box label
7FSCRxxxx$M1
7FSCRxxxx$T1
19 REFERENCE SPECIFICATION
ST7SCR Datasheet 1.3 (March 2003).
20 SILICON LIMITATIONS
20.1 UNEXPECTED RESET FETCH
If an interrupt request occurs while a "POP CC" instruction is executed, the interrupt controller
does not recognise the source of the interrupt and, by default, passes the RESET vector ad-
dress to the CPU.
To solve this issue, a "POP CC" instruction must always be preceded by a "SIM" instruction.
20.2 USB: TWO CONSECUTIVE SETUP TOKENS
Description
When two consecutive SETUP tokens are received and the software does not have time to
write the value 8 in the Endpoint 0 Reception Counter Register (CNT0RXR), the data associ-
ated with the second SETUP are not copied to the buffer.
Impact
The impact depends on the host behaviour. In the USB Spec 2.0 it is stated (chapter 5.5.5
p43) that: “A Setup transaction should not normally be sent before the completion of a pre-
vious control transfer. However, if a transfer is aborted, for example, due to errors on the bus,
the host can send the next Setup transaction prematurely from the endpoint’s perspective”. If
the new Setup token is sent because an error occurs in the previous one, it should contain the
same data so no application malfunction will occur.
March 2003
Rev. 1.2
99/102