Z86D990 Datasheet, PDF (9/102 Pages) Zilog, Inc. – Low-Voltage Micro controllers with ADC

Z86D990/Z86D991 OTP and Z86L99X ROM
Low-Voltage Microcontrollers with ADC
2
The Z8 instruction set, consisting of 43 basic instructions, is optimized for high-
code density and reduced execution time. It is similar in form to the ZiLOG Z80
instruction set. The eight instruction types and six addressing modes together
with the ability to operate on bits, 4-bit nibbles or binary coded decimal (BCD) dig-
its, 8-bit bytes, and 16-bit words, make for a code-efficient, flexible microcontroller.
Features
• Four-channel, 8-bit sigma delta analog-to-digital (A/D) converter with external
voltage references (not available in the 28-pin configuration)
• Two independent analog comparators
• Controlled current output
• 489 bytes of RAM
– 233 bytes of general-purpose register-based RAM
– 256 bytes of RAM mapped into the program memory space that can be
used as data RAM or executable RAM
• 32 Kbytes of OTP memory (Z86D99X)
• 16 Kbytes of ROM (Z86L99X)
Counter/Timers
• Special architecture to automate generation and reception of complex pulses
or signals:
– Programmable 8-bit counter/timer (T8) with two 8-bit capture registers and
two 8-bit load registers
– Programmable 16-bit counter/timer (T16) with one 16-bit capture register
pair and one 16-bit load register pair
– Programmable input glitch filter for pulse reception
• One general-purpose 8-bit counter/timer (T1) with 6-bit prescaler
Input/Output and Interrupts
• Thirty-two I/Os, twenty-nine of which are bidirectional I/Os with programmable
resistive pull-up transistors (24 I/Os are available in the 28-pin configuration)
• Sixteen I/Os are selectable as stop-mode recovery sources
• Six interrupt vectors with nine interrupt sources
– Three external sources
– Two comparator interrupts
PS003807-1002
PRELIMINARY