T89C51CC01UA-RLTIM Atmel, T89C51CC01UA-RLTIM Datasheet - Page 8

• Manufacturer Part Number: T89C51CC01UA-RLTIM
• Description: IC 8051 MCU FLASH 32K 44VQFP
• Manufacturer: Atmel
• Series: AT89C CANr

Specifications of T89C51CC01UA-RLTIM

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: CAN, UART/USART
• Peripherals: POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: FLASH
• Eeprom Size: 2K x 8
• Ram Size: 1.25K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-TQFP, 44-VQFP
• For Use With: AT89STK-06 - KIT DEMOBOARD 8051 MCU W/CAN
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: T89C51CC01UARLTIM

Active UART Bootloader Errata List
• Timer 2 and UART Are Not Stopped
• Watchdog and Flash API Starting the Bootloader Execution
• Autobaud False Start Bit Detection
• Boot Process Compatibility
• Flash API ’__api_wr_code_page’ with 0 Data in Length Parameter Field
UART Bootloader Errata History
UART Bootloader Errata Description
1. Timer 2 and UART Are Not Stopped
2. Watchdog and Flash API Starting the Bootloader Execution
3. Autobaud False Start Bit Detection
4. Boot Process Compatibility
8
Version Number
1.2 (1.1.2 displayed by FLIP)
1.4 (Current)
When the bootloader receives the command ’Start Application’ (LJMP 0), the Timer 2 and the UART are not stopped.
Workaround
The application must have in its setup function a reset of Timer 2 and UART.
When an application call ’__api_start_bootloader’ or ’__api_start_isp’ routines while the watchdog is enabled, when the
watchdog overflows it will restart the application instead of the bootloader.
Workaround
Set BLJB(=1) before calling the __api_start_bootloader or __api_start_isp if the watchdog is used.
UART autobaud sequence does not work in some special UARTs.
Some laptops have the UART TX line set to 0 when unused (COM port closed), this results in a false baud rate calcu-
lation in the ‘U’ character.
The autobaud sequence checkes for a ‘0’ state (not a falling edge) on the Rx line of the UART microcontroller to detect
the ‘start’ bit of the ‘U’ synchro character.
As this line is ‘0’ by default when COM port is closed, the autobaud routine starts its baudrate calculation at the opening
sequence of the UART.
Workaround
A ‘Special Sync’ can be used with ‘FLIP’ software.
In this case, the open port event and the ‘U’ sent are dissociated. The user must first open the COM port with the ‘con-
nect’ button, then reset the hardware and finally push the ‘sync’ button.
There are some differences between Boot process of bootloader 1.2 and newer versions (see below).
mov SCON, #00h
mov T2CON, #00h
mov RCAP2L, #00h
mov RCAP2H, #00h
mov TL2, #00h
mov TH2, #00h
T89C51CC01 Errata Sheet
Errata List
1, 2, 3
1, 2, 3, 4,5
4131J–CAN–05/06