ez80: some additional comments for the ez80 cpu driver

This commit is contained in:
Dean Netherton
2024-09-15 18:44:15 +10:00
parent 7157d7f11d
commit c31f9de905
2 changed files with 20 additions and 7 deletions

View File

@@ -1,15 +1,28 @@
;
;==================================================================================================
; EZ80 50/60HZ TIMER TICK DRIVER
; RCBUS EZ80 CPU DRIVER
;==================================================================================================
;
; Communicate with on-chip eZ80 firmware to:
; Driver code designed for the RCBus eZ80 CPU Module.
; The driver expects the eZ80 firmware to manage the initial booting of the system.
; Details for the platform and the software for the on-chip firmware can be found at:
; https://github.com/dinoboards/rc2014-ez80
;
; Although the eZ80 firmware is booted before HBIOS, the eZ80 CPU driver is still required
; to communicate with the firmware to perform a number of initialisation tasks.
; See also the associated ez80 platform drivers (ez80rtc, ez80systmr, ez80uart).
;
; The driver 'exports' two key functions:
; 1. EZ80_PREINIT - This function is called by the HBIOS boot code to initialise the eZ80 firmware.
; 2. EZ80_RPT_TIMINGS - This function is called by the HBIOS boot code to report the platform timings.
;
; EZ80_PREINIT performs the following:
; 1. Exchange platform version numbers
; 2. Configure memory banking type
; 3. Retrieve CPU Frequency
; 4. Set Memory and I/O Bus Timings
; 5. Set Timer Tick Frequency
; 2. Retrieve CPU Frequency
; 3. Set Memory and I/O Bus Timings
; 4. Set Timer Tick Frequency
;
EZ80_PREINIT:
EZ80_TMR_INT_DISABLE()

View File

@@ -1,6 +1,6 @@
;
;==================================================================================================
; EZ80 ON-CHIP CLOCK DRIVER
; EZ80 ON-CHIP RTC DRIVER
;==================================================================================================
;
EZ80RTC_BUFSIZ .EQU 6 ; SIX BYTE BUFFER (YYMMDDHHMMSS)