User`s manual

EM Microelectronic EM6812 microcontrollers
Following signals are use for In-system programming of
EM6812 microcontrollers.
RESET reset
TEST/VPP switch to programming mode
SCLK(PB5) clock
SDIO(PB7) data input / output
VDD power supply
VSS ground
SDIO(PB7) and SCLK(PB5) signals are used by the EM6812
for In-system programming, therefore target system mustn’t
affect these signals during In-system programming to avoid
programming errors.
B+K PRECISION’s recommended circuit for EM6812:
R1
10k
R2
10k
VSS
C1
22n
VSS
VSS
VDD
SCLK(PB5)
SDIO(PB7)
RESET
TEST/VPP
VSS
I1
EM6812
SDIO(PB7)
SCLK(PB5)
TEST/VPP
VDD
RESET
R6
10k
VSS
VSS
D2
1N4148
R11
100k
C2
1u/10V
+3,3V
D3
BAT85
ISP connector target device target system
reset circuit
D3 is optional
diode, if VDD
from
programmer
is used
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