ra8_time_constants.h File Reference

Named Time Unit Constants for Delay / Timeout / Tick Math. More...

#include <stdint.h>

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Enumerations
enum	ra8_time_unit_t : uint32_t {   k_ra8_ns_per_us = 1000UL ,   k_ra8_us_per_ms = 1000UL ,   k_ra8_ms_per_sec = 1000UL ,   k_ra8_ns_per_ms = 1000000UL ,   k_ra8_us_per_sec = 1000000UL ,   k_ra8_ns_per_sec = 1000000000UL ,   k_ra8_sec_per_min = 60UL ,   k_ra8_min_per_hour = 60UL ,   k_ra8_hour_per_day = 24UL ,   k_ra8_sec_per_hour = 3600UL ,   k_ra8_sec_per_day = 86400UL }
	Integer conversion factors between common time units. More...
enum	ra8_clock_hz_t : uint32_t {   k_ra8_xtal_hz = 24000000UL ,   k_ra8_loco_hz = 32768UL ,   k_ra8_moco_hz = 8000000UL ,   k_ra8_hoco_hz = 20000000UL ,   k_ra8_pll1p_hz = 1000000000UL ,   k_ra8_pll1q_hz = 333333333UL ,   k_ra8_pll1r_hz = 400000000UL ,   k_ra8_cpuclk0_hz = 1000000000UL ,   k_ra8_cpuclk1_hz = 250000000UL ,   k_ra8_iclk_hz = 250000000UL ,   k_ra8_pclka_hz = 125000000UL ,   k_ra8_pclkb_hz = 62500000UL ,   k_ra8_pclkc_hz = 125000000UL ,   k_ra8_pclkd_hz = 250000000UL ,   k_ra8_pclke_hz = 250000000UL ,   k_ra8_bclk_hz = 125000000UL ,   k_ra8_fclk_hz = 125000000UL ,   k_ra8_mriclk_hz = 250000000UL ,   k_ra8_iclk_max_hz = 250000000UL }
	Expected clock frequencies after PLL bring-up. More...
enum	ra8_timeout_ms_t : uint32_t {   k_ra8_timeout_none_ms = 0UL ,   k_ra8_timeout_short_ms = 10UL ,   k_ra8_timeout_default_ms = 100UL ,   k_ra8_timeout_long_ms = 1000UL ,   k_ra8_timeout_very_long_ms = 10000UL }
	Canonical timeouts used across drivers. More...

Detailed Description

Named Time Unit Constants for Delay / Timeout / Tick Math.

Collects every magic number related to time (microseconds, milliseconds, Hz) into a single typed-enum vocabulary so firmware code never writes a raw 1000, 1000000, or 0.001f.

Example rewrite:

// BAD: reader has to decode the arithmetic
for (uint32_t i = 0; i < 240 * 1000; i++) { ... }
 
// GOOD: the intent is in the constant names
for (uint32_t i = 0; i < k_ra8_cpu_mhz * k_ra8_us_per_ms; i++) { ... }

Copyright

Copyright (c) 2026 Brighton Sikarskie SPDX-License-Identifier: MIT

Definition in file ra8_time_constants.h.

Enumeration Type Documentation

ra8_clock_hz_t

enum ra8_clock_hz_t : uint32_t

Expected clock frequencies after PLL bring-up.

These are the target values the CGC driver programmes. Real-world values are measured at runtime via the CAC (Clock Accuracy Check) and validated to be within +/- 0.1% before any time-critical peripheral is enabled. Adjust here and the CGC driver will follow.

Note

The main Cortex-M85 core runs at k_ra8_cpuclk0_hz; the secondary Cortex-M33 runs at k_ra8_cpuclk1_hz from the same PLL. All peripheral clocks are derived dividers of the PLL.

Enumerator
k_ra8_xtal_hz	24 MHz main crystal on EK-RA8D2.
k_ra8_loco_hz	Low-speed on-chip oscillator.
k_ra8_moco_hz	Middle-speed on-chip oscillator.
k_ra8_hoco_hz	High-speed on-chip oscillator.
k_ra8_pll1p_hz	PLL1P = (24/3)*250/2 = 1000 MHz.
k_ra8_pll1q_hz	PLL1Q = (24/3)*250/6 ~= 333 MHz.
k_ra8_pll1r_hz	PLL1R = (24/3)*250/5 = 400 MHz.
k_ra8_cpuclk0_hz	CPUCLK0 = PLL1P/1 = 1 GHz.
k_ra8_cpuclk1_hz	CPUCLK1 = PLL1P/4 = 250 MHz.
k_ra8_iclk_hz	ICLK = PLL1P/4 = 250 MHz.
k_ra8_pclka_hz	PCLKA = PLL1P/8 = 125 MHz.
k_ra8_pclkb_hz	PCLKB = PLL1P/16 = 62.5 MHz.
k_ra8_pclkc_hz	PCLKC = PLL1P/8 = 125 MHz.
k_ra8_pclkd_hz	PCLKD = PLL1P/4 = 250 MHz.
k_ra8_pclke_hz	PCLKE = PLL1P/4 = 250 MHz.
k_ra8_bclk_hz	BCLK = PLL1P/8 = 125 MHz.
k_ra8_fclk_hz	FCK (MRPCLK) = PLL1P/8 = 125 MHz.
k_ra8_mriclk_hz	MRICLK = PLL1P/4 = 250 MHz (MRAM I/F).
k_ra8_iclk_max_hz	Highest ICLK the part is rated for. This is a DEVICE LIMIT, not the configured rate: it is the denominator in HUM Ch 58.3.7 "Wait State" p 3540, where SRAMWTSC.WTEN must be set once ICLK exceeds half of it. R7KA8D2KFLCAC is a 250 MHz-ICLK part; the 200 MHz and 150 MHz classes in that section belong to other RA8 variants.

Definition at line 74 of file ra8_time_constants.h.

ra8_time_unit_t

enum ra8_time_unit_t : uint32_t

Integer conversion factors between common time units.

Enumerator
k_ra8_ns_per_us	Nanoseconds per microsecond.
k_ra8_us_per_ms	Microseconds per millisecond.
k_ra8_ms_per_sec	Milliseconds per second.
k_ra8_ns_per_ms	Nanoseconds per millisecond.
k_ra8_us_per_sec	Microseconds per second.
k_ra8_ns_per_sec	Nanoseconds per second.
k_ra8_sec_per_min	Seconds per minute.
k_ra8_min_per_hour	Minutes per hour.
k_ra8_hour_per_day	Hours per day.
k_ra8_sec_per_hour	Seconds per hour.
k_ra8_sec_per_day	Seconds per day.

Definition at line 41 of file ra8_time_constants.h.

ra8_timeout_ms_t

enum ra8_timeout_ms_t : uint32_t

Canonical timeouts used across drivers.

Centralised so the whole firmware agrees on "short", "default", "long" timeouts. Individual drivers may override for good reason but the default should come from here.

Enumerator
k_ra8_timeout_none_ms	Poll once, never block.
k_ra8_timeout_short_ms	10 ms – quick bus op.
k_ra8_timeout_default_ms	100 ms – default.
k_ra8_timeout_long_ms	1 s – slow devices.
k_ra8_timeout_very_long_ms	10 s – boot / recovery.

Definition at line 115 of file ra8_time_constants.h.