SAB80515 Datasheet, PDF (13/270 Pages) Siemens Semiconductor Group – 8-Bit Single-Chip Microcontroller Family

Fundamental Structure
2.1 Differences between MYMOS (SAB 80515/80535) and
ACMOS (SAB 80C515/80C535) Versions
There are some differences between MYMOS and ACMOS versions concerning:
– Power Saving Modes
– Special Function Register PCON
– Port Driver Circuitry
– A/D Converter Input Ports
– A/D Converter Conversion Time
– Oscillator and Clock Circuit
– V_BB Pin
2.1.1 Power Saving Modes
The SAB 80515/80535 has just the power-down mode, which allows retention of the on-chip RAM
contents through a backup supply connected to the V_PD pin.
The SAB 80C515/80C535 additionally has the following features:
– idle mode
– the same power supply pin V_CC for active, power-down and idle mode
– an extra pin (PE) that allows enabling/disabling the power saving modes
– starting of the power-saving modes by software via special function register PCON (Power
Control Register)
– protection against unintentional starting of the power-saving modes
These items are described in detail in section 7.6.
2.1.2 Special Function Register PCON
In the MYMOS version SAB 80515/80535 the SFR PCON (address 87H) contains only bit 7
(SMOD).
In the ACMOS version SAB 80C515/80C535 there are additional bits used (see figure 2-2).
The bits PDE, PDS and IDLE, IDLS select the power-down mode or idle mode, respectively, when
the power saving modes are enabled by pin PE.
Furthermore, register PCON of the ACMOS version contains two general-purpose flags. For
example, the flag bits GF0 and GF1 can be used to indicate whether an interrupt has occurred
during normal operation or during idle. Then an instruction that activates idle can also set one or
both flag bits. When idle is terminated by an interrupt, the interrupt service routine can sample the
flag bits.
Semiconductor Group
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