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What are the differences between HC11 & and the new HCS08? Your response is appreciated. Regards Leo |
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HC11 vs HCS08?
Started by ●February 4, 2004
Reply by ●February 5, 20042004-02-05
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drleonardok wrote: > What are the differences between HC11 & and the new HCS08? The HC(S)08 CPU has less registers which can be a pain when programing in assembler. Using a compiler, you won't notice this, and the overalls speed is higher (most times) due to the higher bus clock. HC(S)08 has more available derivatives with Flash memory. HCS08 has BDM which makes debugging much better, but also more expensive: there is no cheap way to program the chip as it is possible with HC11 and HC08. Oliver -- Oliver Betz, Muenchen |
Reply by ●February 5, 20042004-02-05
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I used the HC11 for half a dozen project 5 to 10 years ago. Right now, I am finishing two projects that use the HCS08 (9S08GT32) and two that use a regular HC08 (908JB8). The HCS08 parts in volume are starting to compete with some of the 8051's and other more inexpensive micro's. The HC08 core does not have many registers, just A and X or A and HX (a 16 bit index register). The HC11 has the A&B/D registers and another index Y. If you write in assembler and try to do some 16 bit math, you might notice the difference. In C, you won't. The HCS08 has flash, BDM, and a very versatile clock. You can run the clock from an internal oscillator or an external crystal. The internal PLL produces a little bit of dithe, but is not an issue for most applications. The HCS08 bus clock will run up to 20MHz. If I remember correctly, the HC11 internal clock only ran at 4-5MHz, but that was years ago. The varient that I am using has the usual basic peripherals, two timers, two uarts, spi, 8/10bit ADC. It also has some very low current shutdown modes that are useful for battery powered applications. It will also run at lower voltages, down to 1.8VDC. The RTI clock on the HCS08 is a little annoying. It is not accurate at all (+/- 30%) without an external crystal and it will only run in stop modes, which don't work with debugging. The all internal clock is very nice when board area is tight. But if you are depending on maintaining time for a battery based application, you will probably need an external crystal. Motorola was offering the Metrowerks compiler and debugger for free, with a 4K object code limit. I needed to upgrade to the 32K version for one of my applications. My P&E Micro debugger pod cost about $300. That's my 2 cents, Sheldon ----- Original Message ----- From: "drleonardok" <> To: <> Sent: Wednesday, February 04, 2004 6:59 PM Subject: [m68HC11] HC11 vs HCS08? > What are the differences between HC11 & and the new HCS08? > Your response is appreciated. > > Regards > Leo > Yahoo! Groups Links |
Reply by ●February 5, 20042004-02-05
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In a message dated 2/5/04 3:06:04 PM Eastern Standard Time, writes: If I remember correctly, the HC11 internal clock only ran at 4-5MHz, but that was years ago. The HC11F1 doesnt have multiplexed data and address bus... it comes in a 5MHz bus version (20MHz xtal), so except for the lack of flash, could compete with 8051s, AVRs, etc |
