Z86E3412VSG Zilog, Z86E3412VSG Datasheet - Page 56

• Manufacturer Part Number: Z86E3412VSG
• Description: IC MICROCONTROLLER 16K 28-PLCC
• Manufacturer: Zilog
• Series: Z8®r

Specifications of Z86E3412VSG

• Core Processor: Z8
• Core Size: 8-Bit
• Speed: 12MHz
• Connectivity: EBI/EMI
• Peripherals: POR, WDT
• Number Of I /o: 24
• Program Memory Size: 16KB (16K x 8)
• Program Memory Type: OTP
• Ram Size: 237 x 8
• Voltage - Supply (vcc/vdd): 3.5 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 28-PLCC
• Processor Series: Z86E3xx
• Core: Z8
• Data Bus Width: 8 bit
• Data Ram Size: 237 B
• Maximum Clock Frequency: 12 MHz
• Number Of Programmable I/os: 24
• Number Of Timers: 2
• Operating Supply Voltage: 3.5 V to 5.5 V
• Maximum Operating Temperature: + 70 C
• Mounting Style: SMD/SMT
• Development Tools By Supplier: Z86E4400ZDV, Z86E4400ZDP, Z86E4400ZDF, Z86E3400ZDV, Z86E3400ZDS, Z86E3400ZDP
• Minimum Operating Temperature: 0 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Data Converters: -
• Lead Free Status / Rohs Status: Details

®
CMOS Z8
OTP Microcontrollers
Product Specification
52
RAM Protect. The upper portion of the RAM’s address spaces 80h to EFh (excluding the
control registers) can be protected from reading and writing. This option can be selected
during the EPROM Programming Mode. After this option is selected, the user can activate
this feature from the internal EPROM. D6 of the IMR control register (R251) is used to
turn off/on the RAM protect by loading a 0 or 1, respectively. A “1” in D6 indicates RAM
Protect enabled.
Stack. The Z86E43/743/E44 external data memory or the internal register file can be used
for the stack. The 16-bit Stack Pointer (R254-R255) is used for the external stack, which
can reside anywhere in the data memory for ROMless mode, but only from 4096/8192/
16384 to 65535 in ROM mode. An 8-bit Stack Pointer (R255) is used for the internal stack
on the Z8 that resides within the 236 general-purpose registers (R4-R239). SPH (R254)
can be used as a general-purpose register when using internal stack only. R254 and R255
are set to 00H after any reset or Stop Mode Recovery.
Counter/Timers. There are two 8-bit programmable counter/timers (T0 and T1), each
driven by its own 6-bit programmable prescaler. The Ti prescaler is driven by internal or
external clock sources; however, the TO prescaler is driven by the internal clock only (see
Figure
27).
The 6-bit prescalers can divide the input frequency of the clock source by any integer
number from 1 to 64. Each prescaler drives its counter, which decrements the value (1 to
256), that has been loaded into the counter. When the counter reaches the end of count, a
timer interrupt request, IRQ4 (T0) or IRQ5 (T1), is generated.
The counters can be programmed to start, stop, restart to continue, or restart from the ini-
tial value. The counters can also be programmed to stop upon reaching one (single pass
mode) or to automatically reload the initial value and continue counting (modulo-n contin-
uous mode).
The counters, but not the prescalers, can be read at any time without disturbing their value
or count mode. The clock source for T1 is user-definable and can be either the internal
microprocessor clock divided by four, or an external signal input through Port 3. The
Timer Mode register configures the external timer input (P31) as an external clock, a trig-
ger input that can be retriggerable or non-retriggerable, or as a gate input for the internal
clock. Port 3 line P36 serves as a timer output (T
) through which T0, T1, or the inter-
OUT
nal clock can be output. The counter/timers can be cascaded by connecting the T0 output
to the input of T1.
PS022901-0508
Electrical Characteristics