ST10F280-AB 16-Bit MCU with 512K Byte FLASH and 18K Byte RAM Memories ERRATA SHEET 1 - DESCRIPTION This errata sheet describes the functional and electrical problems known in the revision AB of the ST10F280-AB engineering samples. The ST10F280-AB engineering samples marked as EAB-xxxx are not completely tested in all electrical and functional characteristics and should be used for functional evaluation only. Test conditions for these engineering samples are: â TA Room Temperature (25°C) â Vcc 5.0V ±10% â Fosc 40MHz, PLL disabled, direct drive (fCPU = 40MHz) 2 - FUNCTIONAL PROBLEMS The following malfunctions are known in this step: 2.1 - PWRDN.1 - Execution of PWRDN Instruction When instruction PWRDN is executed while pin NMI is at a high level (if PWRDCFG bit is clear in SYSCON register) or while at least one of the port 2 pins used to exit from power-down mode (if PWRDCFG bit is set in SYSCON register) is at the active level, power down mode is not entered, and the PWRDN instruction is ignored. However, under the conditions described below, the PWRDN instruction is not ignored, and no further instructions are fetched from external memory, i.e. the CPU is in a quasi-idle state. This problem only occurs in the following situations: a) The instructions following the PWRDN instruction are located in an external memory, and a multiplexed bus configuration with memory tristate waitstate (bit MT-TCx = 0) is used. Or b) The instruction preceeding the PWRDN instruction writes to external memory or an XPeripheral (XRAM,CAN), and the instructions following the PWRDN instruction are located in external memory. In this case, the problem occurs for any bus configuration. Note: The on-chip peripherals are still working correctly, in particular the Watchdog Timer, if not disabled, resets the device upon an overflow. Interrupts and PEC transfers, however, cannot be processed. In case NMI is asserted low while the device is in this quasi-idle state, power-down mode is entered. No problem occurs if the NMI pin is low (if PWRDCFG = 0) or if all P2 pins used to exit from power-down mode are at inactive level (if PWRDCFG = 1): the chip normally enters powerdown mode. Workaround: Ensure that no instruction that writes to external memory or an XPeripheral preceeds the PWRDN instruction, otherwise insert a NOP instruction in front of PWRDN. When a multiplexed bus with memory tristate wait state is used, the PWRDN instruction must be executed from internal RAM or XRAM. February 2002 This is advance information on a new product now in development or undergoing evaluation. Details are subject to change without notice. 1/4 ST10F280-AB 2.2 - MAC.9 - CoCMP Instruction Inverted Operands The ST10 Family Programming Manual describes the CoCMP instruction as: subtracts a 40-bit signed operand from th 40-bit accumulator content (acc - op2\op1), and updates the N, Z and C flags in the MSW register, leaving the accumulator unchanged. On the device the reverse operation (op2\op1 - acc) has been implemented in the Mac Unit. Therefore, the N and C flags are set according to the reverse operation (Z flag is not affected). Workaround: Change interpretation of the N and C flags in the MSW register. Example: MOV MOV MOV CoLOAD CoCMP R12, #07h R13, #06h R14, #0 R14, R12 R14, R13 ; Accumulator = 70000h ; Compares 70000h to 60000h Here the content of MSW is 0500h, i.e. C = 1, Z = 0 and N = 1. To test if the Accumulator was greater than or equal the compared value, the "normal" test, according to the description in the ST10 Programming Manual, would be: JNB MSW.10, Greater ; If C flag cleared, then greater than or equal With the implementation, this test does not provide the expected result. To obtain the correct comparison, use instead: JB MSW.10, Greater ; C flag set: 60000h < 70000h (60000h-70000h implemented) ; i.e. the accumulator is greater than or equal compared value 2.3 - MAC.10 - E Flag Evaluation for CoSHR and CoASHR Instructions when Saturation Mode is Enabled The Logical and the Arithmetic Right Shift instructions (CoSHR/CoASHR) are specififed not to be affected by the saturation mode (MS bit of the MCW register): the shift operation is always made on the 40 bits of the accumulator. The result shifted in the accumulator is never saturated. Only when the saturation mode is enabled, the evaluation of the E Flag (in the MSW register) is erroneous. Comment to the example: In the example below (Table 1), the E Flag is kept cleared however MAE is used: bit 0 of MAE has been shifted into bit 15 of MAH. The MAE part has been used and it contents significant bits but the E Flag has not been set. The content of the flags is given after the execution of the instruction. Table 1 : MAC.10 Example MS Bit is Set, Saturation Mode is Enabled Accumulator Value (Hexa.) Code MOV R5, #5555h -- CoLOAD R5, R5 00 NOP 00 MOV MSW, #007Fh NOP CoSHR 7F 7F #1 3F ---5555 5555 5555 5555 AAAA ---5555 5555 5555 5555 AAAA Status of Flags After Instruction Execution SL E SV C Z N Remark - - - - - - - 0 0 0 0 0 0 Right 0 0 0 0 0 0 Right 0 0 0 0 0 0 Right 0 0 0 0 0 0 Right 0 0* 0 0 0 0 *E is wrong Workaround: If the MAE flag is used, the saturation mode must be disabled before running Logical and/or Arihmetic Right Shift instructions and re-enable just after. 2/4 ST10F280-AB 2.4 - ST_XTIMER.01 - XADCINJ Signal Output Too Short for ADC Channel Injection The duration of the XADCINJ output lasts two cycles (50ns at 40MHz) but to ensure that a signal transition is properly recognized, an external capture input signal should be held for at least 8 CPU clock cycles before it changes its level so the duration of the XADCINJ signal is too short. Figure 1 : XADCINJ Timing XCLK XADCINJ 4 TCL = 50ns Workaround: The falling edge of the XADCINJ signal must be delayed up to 8 CPU clock cycles. Figure 2 : External Connection for ADC Channel Injection Clock P7.7/CC31 CAPCOM2 UNIT Input Latch Output trigger for ADC channel injection XTIMER XADCINJ R C Typical value: R = 10KâĤ C = 47pF at 40MHz History of Fixed Functional Problems of the ST10F280 Name ST_XADCMUX.01 Short Description Erroneous Conversion Result in Overload Condition Fixed in Step AB Summary of Remaining Functional Problems Known on the ST10F280-AB Name PWRDN.1 Short Description Execution of PWRDN Instruction MAC.9 CoCMP Instruction Inverted Operands MAC.10 E Flag Evaluation for CoSHR and CoASHR Instructions when Saturation Mode is Enabled ST_XTIMER.01 XADCINJ Signal Output Too Short for ADC Channel Injection 3/4 ST10F280-AB 3 - DEVIATIONS FROM DC/AC PRELIMINARY SPECIFICATION DC Parameters Engineering data are not completly collected yet. AC Timings Engineering data are not completly collected yet. Note on On-Chip Oscillator The XTAL2 output is not designed to provide a valid signal when XTAL1 is supplied by an external clock signal. It may happen, if the external clock signal is not perfectly symetrical and centered on VDD / 2, that XTAL2 signal is not equal to XTAL1. This is due to the design of the oscillator, which has a auto-adaptation gain control dedicated to external crystal. If an external clock signal is directly provided on XTAL1 pin, then leave XTAL2 pin disconnected to achieve the lowest consumption of the on-chip oscillator. 4 - ERRATA SHEET VERSION INFORMATION This document has been released on the 6th of February 2002. It reflects the current silicon status of the ST10F280-AB. Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics. The ST logo is a registered trademark of STMicroelectronics STMicroelectronics GROUP OF COMPANIES Australia - Brazil - Canada - China - Finland - France - Germany - Hong Kong - India - Israel - Italy - Japan - Malaysia - Malta - Morocco Singapore - Spain - Sweden - Switzerland - United Kingdom - United States http://www.st.com 4/4 F280-AB.REF © 2002 STMicroelectronics - All Rights Reserved