Errata Sheet TS87C51RC2, TS80C51RC2 This errata sheet describes the functional deviations known at the release date of this document. Errata History TS87C51RC2 Lot Number Trouble list Status ≤ Z36736 T01, T02 ,T03, T04, T05, T06 Not Fixed > Z36736 T02 ,T03, T04, T05, T06 Not Fixed TS80C51RC2 Lot Number Trouble list Status ≤ Z38711 T01, T02 ,T03, T04, T05, T06 Not Fixed > Z38711 T02 ,T03, T04, T05, T06 Not Fixed Trouble descriptions T01 UART / Reception in modes 1, 2 and 3 / UART false start bits detection Description: Workaround: When a false start bit occurs on the UART, some UART internal signals are not reset. Than when a real start bit occurs, the sampling is shifted. No T02 During UART reception, clearing REN may generate unexpected IT Description: During Uart reception, if the REN bit is clear between a start bit detection and the end of reception, the Uart will not discare the data (RI is set). Test REN at the beginning of Interrupt routine just after CLR RI, and to run the Interrupt routine code only if REN is set. Workaround: T03 JBC / Double IT when ext. IT occurs during JBC instruction Description: Workaround: On polling algorithm in ISR on IE1 or IE0, when external IT appears during JBC instruction , flag is not cleared and next JBC see another IT, then the same IT is seen twice. Use JB Instruction instead of JBC instruction to test bit and CLR instruction to clear it.n twice. T04 Timer2 / Downcounter mode / Double IT with slow external clock Description: Double IT with slow external clock in downcount mode.Timer 2 in 16 bit autoreload in count down mode with external clock input 2 interrupts are generated successively with low frequency on clock input (typ 10-40KHz). Reload FFFE into TH2-TL2 in ISR and count down to RCAP-1 (to recover cycle lost in ISR) Workaround: Caution : do not work if initially RCAP = 0x0000 Rev A - 29-Mar-01 1 Errata Sheet T05 Input Trigger Consumption / All C51 type I/O ports Description: Workaround: Some static consumption in input triggers of I/O ports may occur when entries are driven close to the trigger threshold (1mA to 2mA for each I/O at Vin = 2.4V for Vcc = 5V) No T06 Movx / Port0 / Read mode Description: When reading External Ram using Movx instruction, Port0’s Sfr may contain ’0’ whereas any acces to external memories (data or program) should write ’1’ into them . No Workaround: 2 Rev A - 29-Mar-01