Dataman 448PRO2, Руководство пользователя, Страница: 162 / 168

162
DATAMAN recommended circuit for AT89Sxxx:
ISP connector target device target system
reset circuit
R2
R3
GND
C1
22n
GND
VCC
GND
D2
1N4148
GND
VCC
SCK
MISO
GND
I1
AT89Sxxx
DATA OUT
SCK
RST
R1
MOSI
DATA IN
R11
100k
C2
1u/10V
RST
GND
GND
target VCC check only
PICmicro
®
microcontrollers
This interface corresponds with Microchip application notes TB013, TB017, TB016: How to
Implement ICSP
TM
Using PIC16CXXX OTP (PIC12C5XX OTP) (PIC16F8X Flash) MCUs.
These application notes describes requirement for target system with In-system programming
device and ISP programmer.
Following signals are use for In-system programming of PICmicro
®
microcontrollers.
MCLR\ / VPP reset / switch to programming mode
RB6 (GP1)
clock
RB7 (GP0) data input / output
VDD power supply
GND ground
When PICmicro
®
device is programmed; pin MCLR\ / VPP is driven to approximately 12 V.
Therefore, the target system must be isolated from this voltage provided by programmer.
RB6 and RB7 signals are used by the PICmicro
®
for In-system programming; therefore target
system mustn’t affect these signals during In-system programming to avoid programming
errors.
Marginal verify is used after programming. Programmer must verify the program memory
contents at both minimal and maximal power supply, therefore VDD pin of PICmicro
®
must be
isolated from rest of target system during programming.