HD404344R Datasheet, PDF (82/102 Pages) Renesas Technology Corp – 4-bit microcomputer has an A/D converter

HD404344R Series/HD404394 Series
Programmable ROM Operation
The HD4074344 and HD4074394 on-chip PROMs are programmed in PROM mode.
In PROM mode, the MCU does not operate. It can be programmed like a standard 27256 EPROM using a
standard PROM programmer and a socket adapter as shown in figure 61. Table 23 lists the recommended
PROM programmers and socket adapters.
Since instructions of the HMCS400 series consists of 10 bits, the HMCS400 series microcomputers
incorporate a conversion circuit to enable the use of a general-purpose PROM programmer. By this circuit,
an instruction is read or written to using two addresses, lower five bits and upper five bits. For example, if
4 kwords of on-chip PROM are programmed by a general-purpose PROM programmer, 8 kbytes of
addresses ($0000–$1FFF) should be specified.
CE, OE
A₁₂–A₀
Control signals
2 A₁₄ , A₁₃
A₁₂–A₀
A₁₄–A_{0 Address bus}
O₄–O₀
X_ON
M₀
RESET
V_CC
GND
V_PP
HD4074344
HD4074394
3 O₇–O₅
O₄–O₀
O₇–O₀ Data bus
28-to-28-pin socket adapter
30-to-28 pin socket adapter
Figure 61 PROM Mode Connections
V_CC
GND
V_PP
PROM programmer
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