Z86D990 Datasheet, PDF (17/102 Pages) Zilog, Inc. – Low-Voltage Micro controllers with ADC

Z86D990/Z86D991 OTP and Z86L99X ROM
Low-Voltage Microcontrollers with ADC
10
• Interrupt Control (IPR, IMR, and IRQ)
• Stop Mode Recovery (SMR, P2SMR, and P5SMR)
• Low-Battery Detect (LB) Flag
The Z8 uses a 16-bit Program Counter (PC) to determine the sequence of current
program instructions. The PC is not an addressable register.
Peripheral registers are used to transfer data, configure the operating mode, and
control the operation of the on-chip peripherals. Any instruction that references
the register file can access the peripheral registers. The following are peripheral
control registers:
• Analog/Digital Converter (ADCCTRL and ADCDATA)
• T1 Timer/Counter (TMR, T1, and PRE1)
• T8 Timer/Counter (CTR0, HI8, LO8, TC8H, and TC8L)
• T16 Timer/Counter (CTR2, HI16, LO16, TC16H, and TC16L)
• T8/T16 Control Registers (CTR1and CTR3)
In addition, the four port registers are considered to be peripheral registers. The
following are port control registers:
• Port Configuration Registers (P456CON and P3M)
• Port 2 Control and Mode Registers (P2 and P2M)
• Port 4 Control and Mode Registers (P4 and P4M)
• Port 5 Control and Mode Registers (P5 and P5M)
• Port 6 Control and Mode Registers (P6 and P6M)
The functions and applications of the control and peripheral registers are
explained in “Control and Status Registers” on page 52.
Memory (ROM/OTP and RAM)
There are four basic address spaces available to support a wide range of configu-
rations:
• Program memory (on-chip)
• Standard register file
• Expanded register file
• Executable RAM
The Z8 standard register file totals up to 256 consecutive bytes organized as 16
groups of 16 eight-bit registers. These registers consist of I/O port registers,
PS003807-1002
PRELIMINARY