DS87C530-QNL Maxim Integrated Products, DS87C530-QNL Datasheet - Page 28

• Manufacturer Part Number: DS87C530-QNL
• Description: IC MCU EPR/ROM W/RTC 33MZ 52PLCC
• Manufacturer: Maxim Integrated Products
• Series: 87Cr

Specifications of DS87C530-QNL

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 33MHz
• Connectivity: EBI/EMI, SIO, UART/USART
• Peripherals: Power-Fail Reset, WDT
• Number Of I /o: 32
• Program Memory Size: 16KB (16K x 8)
• Program Memory Type: OTP
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 52-LCC, 52-PLCC
• Processor Series: DS87C530
• Core: 8051
• Data Bus Width: 8 bit
• Data Ram Size: 1 KB
• Interface Type: UART
• Maximum Clock Frequency: 33 MHz
• Number Of Programmable I/os: 32
• Number Of Timers: 3
• Operating Supply Voltage: 4.5 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: PK51, CA51, A51, ULINK2
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Data Converters: -
• Other names: DS87C530QNL

TIMED-ACCESS PROTECTION
It is useful to protect certain SFR bits from an accidental write operation. The Timed-Access procedure
stops an errant CPU from accidentally changing these bits. It requires that the following instructions
precede a write of a protected bit.
Writing an AAh and then a 55h to the Timed-Access register (location C7h) opens a three-cycle window
for write access. The window allows software to modify a protected bit(s). If these instructions do not
immediately precede the write operation, then the write will not take effect. The protected bits are:
EPROM PROGRAMMING
The DS87C530 follows standards for a 16kB EPROM version in the 8051 family. It is available in a UV
erasable, ceramic windowed package and in plastic packages for one-time user-programmable versions.
The part has unique signature information so programmers can support its specific EPROM options.
PROGRAMMING PROCEDURE
The DS87C530 should run from a clock speed between 4MHz and 6MHz when programmed. The
programming fixture should apply address information for each byte to the address lines and the data
value to the data lines. The control signals must be manipulated as shown in Table 9. The diagram in
Figure 5 shows the expected electrical connection for programming. Note that the programmer must
apply addresses in demultiplexed fashion to Ports 1 and 2 with data on Port 0. Waveforms and timing are
provided in the Electrical Specifications section. Program the DS87C530 as follows:
1)
2)
3)
4)
5)
6)
Apply the address value,
Apply the data value,
Select the programming option from
Increase the voltage on V
Pulse the PROG signal five times for EPROM array and 25 times for encryption table, lock bits, and other
EPROM bits,
Repeat as many times as necessary.
EXIF.0
WDCON.6
WDCON.1
WDCON.0
WDCON.3
ROMSIZE.2
ROMSIZE.1
ROMSIZE.0
TRIM.7–0
RTCC.2
RTCC.0
PP
from 5V to 12.75V if writing to the EPROM,
MOV
MOV
DS87C530/DS83C530 EPROM/ROM Microcontrollers with Real-Time Clock
Table 9
BGS
POR
EWT
RWT
WDIF
RMS2
RMS1
RMS0
—
RTCWE
RTCE
using the control signals,
28 of 45
0C7h, #0AAh
0C7h, #55h
Bandgap Select
Power-On Reset flag
Enable Watchdog Reset
Restart Watchdog
Watchdog Interrupt Flag
ROM Size Select 2
ROM Size Select 1
ROM Size Select 0
All RTC Trim Functions
RTC Write Enable
RTC Oscillator Enable